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Term Definition
Safe Mode Safe Mode is a way for the Windows operating system to run with the minimum system files necessary. It uses a generic VGA display driver instead of the vendor-specific driver, which means you will likely be working with only 16 colors in a resolution of 640x480. Safe Mode also turns off all third-party drivers for other peripherals such as mice, keyboards, printers, and scanners. In basic Safe Mode, networking files and settings are not loaded, meaning you won't be able to connect to the Internet or other computers on a network. So why would I ever want to boot in Safe Mode? Well, that's a good question. Sometimes, Windows may not fully load after an unexpected crash and the only way to get the computer to boot is to use Safe Mode. Once you have successfully booted the computer in Safe Mode, you can run a disk utility program to repair corrupted files or directories on the hard drive. You can also reboot into Safe Mode to see your display when you get a "Sync Out of Range" message on your screen. There may also be times when your computer is performing sluggishly and becomes annoyingly slow. Booting into Safe Mode will allow you to diagnose the problem and determine which files are slowing down the computer. When calling technical support, the support person may ask you to boot into Safe Mode to begin the troubleshooting. To boot your Windows computer into Safe Mode, hold down the F8 key while the computer is starting up. Then select Safe Mode from the list of boot options.
Samba Most people know of samba as a type of rhythmic dance music from Brazil that uses a 2/4 time signature. In the computer world, samba has a different meaning but is no less exciting (if you are a computer nerd). Samba is an open-source software implementation of the SMB networking protocol used by Windows computers. (If you look closely, you can see the correlation between the two names.) Samba allows other computer platforms, such as Mac OS X, Unix, Linux, IBM System 390, and OpenVMS to interact with Windows computers on the same network. This includes sharing files and using shared devices such as printers connected to other computers within the local network. Because SMB was developed only for Windows, without Samba, other computer platforms would be isolated from Windows machines, even if they were part of the same network. Fortunately, Samba helps different types of computers work together as if they were all based on the same platform. This gives network administrators the freedom to choose multiple types of computers systems when setting up a network. Now that's a reason to dance!
Sample A sample is a digital representation of an analog signal. Both digital video and digital audio files are created using samples. The quality of the sample is determined by the sampling rate, or the bit rate the signal is sampled at. What we see and hear in the real world is in analog format (our bodies process analog information). Computers, on the other hand, can only understand digital information. Therefore, audio and video signals must be converted to a digital format in order to be stored on a computer or saved to a CD or DVD. The converted data is called a sample. The term "sample" is often used to refer to short audio clips used for playing back sounds. For example, a violin sound or a bird chirp may be sampled and then played back from a digital keyboard (or synthesizer). However, samples can refer to entire songs or movies, since the information is technically one long sample. To learn more about how samples are created, view the definition of sampling, which is the process of recording and creating digital samples.
Sampling Before digital recording took over the audio and video industries, everything was recorded in analog. Audio was recorded to devices like cassette tapes and records. Video was recorded to Beta and VHS tapes. The media was even edited in analog format, using multichannel audio tapes (such as 8-tracks) for music, and film reels for video recordings. This method involved a lot of rewinding and fast-forwarding, which resulted in a time-consuming process. Fortunately, digital recording has now almost completely replaced analog recording. Digital editing can be done much more efficiently than analog editing and the media does not lose any quality in the process. However, since what humans see and hear is in analog format (linear waves of light and sound), saving audio and video in a digital format requires converting the signal from analog to digital. This process is called sampling. Sampling involves taking snapshots of an audio or video signal at very fast intervals ? usually tens of thousands of times per second. The quality of the digital signal is determined largely by the sampling rate, or the bit rate the signal is sampled at. The higher the bit rate, the more samples are created per second, and the more realistic the resulting audio or video file will be. For example, CD-quality audio is sampled at 44.1 kHz, or 44,100 samples per second. The difference between a 44.1 kHz digital recording and the original audio signal is imperceptible to most people. However, if the audio was recorded at 22 kHz (half the CD-quality rate), most people would notice the drop in quality right away. Samples can be created by sampling live audio and video or by sampling previously recorded analog media. Since samples estimate the analog signal, the digital representation is never as accurate as the analog data. However, if a high enough sampling rate is used, the difference is not noticeable to the human senses. Because digital information can be edited and saved using a computer and will not deteriorate like analog media, the quality/convenience tradeoff involved in sampling is well worthwhile.
SAN (Storage Area Network) Stands for "Storage Area Network." A SAN is a network of storage devices that can be accessed by multiple computers. Each computer on the network can access hard drives in the SAN as if they were local disks connected directly to the computer. This allows individual hard drives to be used by multiple computers, making it easy to share information between different machines. While a single server can provide a shared hard drive to multiple machines, large networks may require more storage than a single server can offer. For example, a large business may have several terabytes of data that needs to be accessible by multiple machines on a local area network (LAN). In this situation, a SAN could be setup instead of adding additional servers. Since only hard drives need to be added instead of complete computer systems, SANs are an efficient way to increase network storage.
SATA Serial ATA.
SATA (Serial Advanced Technology Attachment) Stands for "Serial Advanced Technology Attachment," or "Serial ATA." It is an interface used to connect ATA hard drives to a computer's motherboard. SATA transfer rates start at 150MBps, which is significantly faster than even the fastest 100MBps ATA/100 drives. For this and other reasons, Serial ATA is likely to replace the previous standard, Parallel ATA (PATA), which has been around since the 1980s. Besides faster transfer rates, the SATA interface has several advantages over the PATA interface. For one, SATA drives each have their own independent bus, so there is no competition for bandwidth like there is with Parallel ATA. They also use smaller, thinner cables, which allows for better airflow inside the computer. SATA cables can be as long as one meter, while PATA cables max out at 40cm. This gives manufacturers more liberty when designing the internal layout of their computers. Finally, Serial ATA uses only 7 conductors, while Parallel ATA uses 40. This means there is less likely to be electromagnetic interference with SATA devices. In summary, Serial ATA is a better, more efficient interface than the dated PATA standard. If you are looking to buy a computer that will support fast hard drives for years to come, make sure it comes with a SATA interface.
Screenshot A screenshot, or screen capture, is a picture taken of your computer's desktop. This may include the desktop background, icons of files and folders, and open windows. It may also include whatever is being displayed by currently running programs. Screenshots are and easy way to save something you see on the screen, such as an open window, image, or text article. However, because screenshots are saved in an image format, the text saved in a screenshot will not be editable. Both the Mac OS and Windows operating systems make it easy to take screenshots. Just use the following keyboard shortcuts to capture the current screen displayed on your computer: Mac OS X: Command-Shift-3: Saves a screenshot of the entire desktop to an image file on the desktop. Command-Shift-4: Saves a screenshot of a selection selected with the cursor to an image file on the desktop. Command-Control-Shift-3: Saves a screenshot of the entire desktop to the clipboard. Command-Control-Shift-4: Saves a screenshot or a selection selected with the cursor to the clipboard. Windows XP: Print Screen: Saves a screenshot of the entire desktop to the clipboard. Alt+Print Screen: Saves a screenshot of the active window to the clipboard.
Script A computer script is a list of commands that are executed by a certain program or scripting engine. Scripts may be used to automate processes on a local computer or to generate Web pages on the Web. For example, DOS scripts and VB Scripts may be used to run processes on Windows machines, while AppleScript scripts can automate tasks on Macintosh computers. ASP, JSP, and PHP scripts are often run on Web servers to generate dynamic Web page content. Script files are usually just text documents that contain instructions written in a certain scripting language. This means most scripts can be opened and edited using a basic text editor. However, when opened by the appropriate scripting engine, the commands within the script are executed. VB (Visual Basic) scripts, for example, will run when double-clicked, using Windows' built-in VB scripting support. Since VB scripts can access and modify local files, you should never run a VB script that you receive as an unknown e-mail attachment.
Scroll Bar When the contents of a window are too large to be displayed entirely within the window, a scroll bar will appear. For example, if a Web page is too long to fit within a window, a scroll bar will show up on the right-hand side of the window, allowing you to scroll up and down the page. If the page is too wide for the window, another scroll bar will appear at the bottom of the window, allowing you to scroll to the left and right. If the window's contents fit within the current window size, the scroll bars will not appear. The scroll bar contains a slider that the user can click and drag to scroll through the window. As you may have noticed, the size of the slider may change for different windows. This is because the slider's size represents what percentage of the window's content is currently being displayed within the window. For example, a slider that takes up 75% of the scroll bar means 75% of the content fits within the current window size. A slider that fills only 10% of the scroll bar means only 10% of the window's contents are being displayed within the current window size. Therefore, if two windows are the same size, the one with the smaller slider has more content than the one with the larger slider. Most scroll bars also contain up and down or left and right arrows that allow the user to scroll in small increments by clicking the arrows. However, clicking and dragging the slider is much faster, so the arrow keys are typically not used as often. Also, some mice have a scroll wheel that allows the user to scroll by dragging the wheel instead of clicking and dragging within the scroll bar.
Scroll Wheel Computer windows are often not large enough to display the entire contents of the window at one time. Therefore, you may need to scroll through the window to view all the contents. Traditionally, this has been done by clicking and dragging the slider within the scroll bar. However, many mice now come with scroll wheels that make the scrolling process even easier. The scroll wheel typically sits between the left and right buttons on the top of a mouse. It is raised slightly, which allows the user to easily drag the wheel up or down using the index finger. Pulling the scroll wheel towards you scrolls down the window, while pushing it away scrolls up. Most modern mice include a scroll wheel, since it eliminates the need to move the cursor to the scroll bar in order to scroll through the window. Therefore, once you get accustomed to using a scroll wheel, it can be pretty difficult to live without. Most scroll wheels only allow the user to scroll up and down. However, some programs allow the user to use a modifier key, such as Control or Shift, to change the scrolling input to left and right. Some mice even have a tilting scroll wheel that allows the user to scroll left and right. The Apple Mighty Mouse has a spherical scrolling mechanism (called a scroll ball) that allows the user to also scroll left and right and even diagonally. Whatever the case, any type of scroll wheel is certainly better than nothing.
Scrolling Most computer programs display their content within a window. However, windows are often not large enough to display their entire content at once. Therefore, you may have to scroll through the window to view the rest of the contents. For example, on some monitors, a page from a word processing document may not fit within the main window when viewed at 100%. Therefore, you may have to scroll down the window to view the rest of the page. Similarly, many Web pages do not fit completely within a window and may require you to scroll both vertically and horizontally to see all the content. To scroll up or down within a window, simply click the scroll bar on the right-hand side of the window and drag the slider up or down. If the window requires horizontal scrolling as well, click the scroll bar at the bottom of the window and drag the slider to the right or left. Some computer mice also include a scroll wheel that allows you to scroll through the window by rolling the wheel back and forth.
SCSI (Small Computer System Interface) Stands for "Small Computer System Interface," and is pronounced "scuzzy." SCSI is a computer interface used primarily for high-speed hard drives. This is because SCSI can support faster data transfer rates than the commonly used IDE storage interface. SCSI also supports daisy-chaining devices, which means several SCSI hard drives can be connected to single a SCSI interface, with little to no decrease in performance.
SD (Secure Digital) Stands for "Secure Digital." It is a type of memory card used for storing data in devices such as digital cameras, PDAs, mobile phones, portable music players, and digital voice recorders. The card is one of the smaller memory card formats, measuring 24mm wide by 32mm long and is just 2.1mm thick. To give the cards some orientation, the top-rght corner of each SD card is slanted. Even though the cards are extremely small, as of late 2004, they can hold up to 8GB of data. Part of the reason the cards are called "Secure Digital" cards is because the cards have a copyright protection feature built in. The security feature, called "key revocation" means protected data on the card can only be read by specific devices. The cards can have both secured and unsecured areas on them for copyrighted and non-copyrighted data. For more information on SD cards, visit the SD Card Association.
SDRAM Synchronous Dynamic Random Access Memory. Is an improvement to standard DRAM.
SDRAM (Synchronous Dynamic Random Access Memory) Stands for "Synchronous Dynamic Random Access Memory." Yeah, it's a mouthful, but if you memorize it, you can really impress your friends. SDRAM is an improvement to standard DRAM because it retrieves data alternately between two sets of memory. This eliminates the delay caused when one bank of memory addresses is shut down while another is prepared for reading. It is called "Synchronous" DRAM because the memory is synchronized with the clock speed that the computer's CPU bus speed is optimized for. The faster the bus speed, the faster the SDRAM can be. SDRAM speed is measured in Megahertz, which makes it easy to compare the processor's bus speed to the speed of the memory.
SDSL (Symmetric Digital Subscriber Line) Stands for "Symmetric Digital Subscriber Line." SDSL is a type of of DSL, which is used for transferring data over copper telephone lines. The "symmetric" part of the term means that an SDSL connection has the same maximum upload and download speeds. ADSL, on the other hand, typically provides much faster download speeds than upload speeds. Because most Internet users download much more data than they upload, ISPs usually offer ADSL connections rather than SDSL.
Search Engine Google, Excite, Lycos, AltaVista, Infoseek, and Yahoo are all search engines. They index millions of sites on the Web, so that Web surfers like you and me can easily find Web sites with the information we want. By creating indexes, or large databases of Web sites (based on titles, keywords, and the text in the pages), search engines can locate relevant Web sites when users enter search terms or phrases. When you are looking for something using a search engine, it is a good idea to use words like AND, OR, and NOT to specify your search. Using these boolean operators, you can usually get a list of more relevant sites.
Sector A sector is the smallest unit that can be accessed on a hard disk. Each platter, or circular disk of a hard disk is divided into tracks, which run around the disk. These tracks get longer as they move from the middle towards the outside of the disk, so there are more sectors along the tracks near the outside of the disk than the ones towards the center of disk. This variance in sectors per track is referred to as "zoned-bit recording." Large files can take up thousands of sectors on a disk. Even if one of these sectors becomes corrupted, the file will most likely be unreadable. While a disk utility program may be able to fix corrupted data, it cannot fix physical damage. Physically damaged sectors are called "bad sectors." While your computer may recognize and bypass bad sectors on your hard disk, certain bad sectors may prevent your disk from operating properly. Yet another good reason to always back up your data!
SEO (Search Engine Optimization) Stands for "Search Engine Optimization." Just about every Webmaster wants his or her site to appear in the top listings of all the major search engines. Say, for example, that Bob runs an online soccer store. He wants his site to show up in the top few listings when someone searches for "soccer shoes." Then he gets more leads from search engines, which means more traffic, more sales, and more revenue. The problem is that there are thousands of other soccer sites, whose Webmasters are hoping for the same thing. That's where search engine optimization, or SEO, comes in. SEO involves a number of adjustments to the HTML of individual Web pages to achieve a high search engine ranking. First, the title of the page must include relevant information about the page. In the previous example, Bob's home page might have the title, "Bob's Soccer Store -- Soccer Shoes and Equipment." The title is the most important part of SEO, since it tells the search engine exactly what the page is about. Within Bob's home page, it would be helpful to repeat the words "soccer" and "soccer shoes" a few times, since search engines also scan the text of the pages they index. Finally, there are META tags. These HTML tags can really distinguish your site from the rest of the pile. The META tags that most search engines read are the description and keywords tags. Within the description tags, you should type a brief description of the Web page. It should be similar but more detailed than the title. Within the keywords tags, you should list 5-20 words that relate to the content of the page. Using META tags can significantly boost your search engine ranking. So what happens when a bunch of sites all have similar titles, content, and META tags? Well, most search engines choose to list the most popular sites first. But then how do you get into the most popular sites? The best way is to submit your site to Web directories (not just search engines) and get other sites to link to yours. It can be a long climb to the top, but your perserverance will pay off. For more tips on SEO, visit the Submit Corner Web site.
Serial Port The serial port is a type of connection on PCs that is used for peripherals such as mice, gaming controllers, modems, and older printers. It is sometimes called a COM port or an RS-232 port, which is its technical name. If that's not enough to confuse you, there are two types of serial ports -- DB9 and DB25. DB9 is a 9-pin connection, and DB25 is, you guessed it, a 25-pin connection. A serial port can only transmit one bit of data at a time, whereas a parallel port can transmit many bits at once. The serial port is typically the slowest port you'll find on a PC, if you find one at all. Most newer computers have replaced serial ports with much faster and more compatible USB ports.
Server As the name implies, a server serves information to computers that connect to it. When users connect to a server, they can access programs, files, and other information from the server. Common servers are Web servers, mail servers, and LAN servers. A single computer can have several different server programs running on it.
Server A computer, or a software package, that provides a specific kind of service to a client software running on other computers.
Service Pack A service pack is a software package that contains several updates for an application or operating system. Individual updates are typically called software updates or patches. When a software company has developed several updates to a certain program or operating system, the company may release all the updates together in a service pack. Many Windows users are familiar with service packs because of the popular service pack released for Windows XP, called SP2. Windows XP SP2 not only included typical updates such as bug fixes and security updates, it added new features. Some of the features included new security tools, interface enhancements to Internet Explorer and Outlook Express, and new DirectX technologies. In fact the SP2 service pack for Windows XP was so comprehensive, many newer Windows programs require it in order to run. Service packs are usually offered as free downloads from the software developer's website. A software update program on your computer may even prompt you to download a service pack when it becomes available. Typically, it is a good idea to download and install new service packs. However, is may also be wise to wait a week or two after the service pack is released to make sure no new bugs or incompatibilities are introduced with the service pack. If you do not have a high-speed Internet connection, you can often purchase a service pack update CD for a small charge. While service packs are commonly released for Microsoft products, not all companies use them. Apple's Mac OS X, for example, uses the Software Update program to install incremental updates to the operating system. Each Mac OS X update includes several small updates to the operating system and bundled applications, much like a service pack.
Shareware There is commercial software and then there is shareware. With commercial software, you have to pay for the product before you use it. With shareware, you can use the product for a trial period and then decide if you want to keep it. If you want to keep the software after the trial period is up, you're supposed to (and should) register the product and pay the shareware fee. As an extra incentive to pay for the software, many shareware programs disable certain features in the non-registered version and some will keep bugging you to register the program after the trial period has expired. Shareware programs are usually less expensive than commercial software programs, but they are usually less expensive to develop as well. This is why shareware programs are typically not as robust as commercial software programs. However, there are numerous shareware programs out there, such as system utilities, that can be very useful. The most common way to get shareware these days is off the Internet. Check out C|net's Shareware.com for a huge selection of these great little programs.
Shell Most people know of shells as small protective coverings for certain animals, such as clams, crabs, and mollusks. You may also find a shell on the outside of an egg, which I highly recommend you remove before eating. In the computer science world, however, a shell is a software program that interprets commands from the user so that the operating system can understand them and perform the appropriate functions. The shell is a command-line interface, which means it is soley text-based. The user can type commands to perform functions such as run programs, open and browse directories, and view processes that are currently running. Since the shell is only one layer above the operating system, you can perform operations that are not always possible using the graphical user interface (GUI). Some examples include moving files within the system folder and deleting files that are typically locked. The catch is, you need to know the correct syntax when typing the commands and you may still be prompted for a password in order to perform administrative functions. Shells are most commonly associated with Unix, as many Unix users like to interact with the operating system using the text-based interface. Two common Unix shells are the Bourne shell and the C Shell, which is used by BSD. Most Unix systems have both of these shells available to the user. Windows users may be more familiar with DOS, the shell that has long been included with the Windows operating system. Most computer users have no need to use the shell interface, but it can be a fun way to perform functions on your computer, as well as impress your friends.
SIMM Single in line memory module.
SIMM (Single In-Line Memory Module) Stands for "Single In-Line Memory Module." This is an older type of computer memory. A SIMM is a small circuit board with a bunch of memory chips on it. SIMMs use a 32-bit bus, which is not as wide as the 64-bit bus dual in-line memory modules (DIMMs) use. Newer processors require a 64-bit memory bus, so it is best to use DIMMs. Sometimes you can get away with installing SIMMS, but they have to be installed in pairs.
Site Map A site map, sometimes written "sitemap," is an overview of the pages within a website. Site maps of smaller sites may include every page of the website, while site maps of larger sites often only include pages for major categories and subcategories of the website. While site maps can be organized in a variety of ways, most use an outline form, with pages arranged by topic. This gives visitors a good overall picture of how the site is organized and clearly defines all the resources the website has to offer. While a properly designed website should allow visitors to navigate the entire site without using the site map, incorporating a site map gives users another means of locating pages. For this reason, each page listed in a site map is typically linked to the page it represents. This allows visitors to quickly jump to any section of a website listed in the site map.
Skin This strange term refers to the appearance of a program's interface. By changing the skin of a program, you can make the interface look completely different, but usually still have all the same functions. It is similar to a "Theme" you may use to customize the appearance of your computer's desktop. Skins have become particularly popular for MP3 players. Because of the simple interface of most MP3 programs, it is easy to create different looks for the interface. Other programs, such as Netscape 6, ICQ, Yahoo Messenger, and Windows Media Player also support skins. If you're one of those people who can't stand seeing the same thing over and over again, skins are for you. Some programs that support skins even provide a skin development kit that your can use to create your own. Though this allows for an unlimited amount of interface customizing, it can make it hard to recognize or use the same program on different computers.
SKU (Stock Keeping Unit) Stands for "Stock Keeping Unit," and is conveniently pronounced "skew." A SKU is a number or string of alpha and numeric characters that uniquely identify a product. For this reason, SKUs are often called part numbers, product numbers, and product identifiers. SKUs may be a universal number such as a UPC code or supplier part number or may be a unique identifier used by a specific a store or online retailer. For example, one company may use the 10 character identifier supplied by the manufacturer as the SKU of an external hard drive. Another company may use a proprietary 6-digit number as the SKU to identify the part. Many retailers use their own SKU numbers to label products so they can track their inventory using their own custom database system. When shopping online or at retail stores, knowing a product's SKU can help you locate the exact product at a later time. It will help you identify a unique product when there are many similar options, such as a TV model that comes in different colors, sizes, etc. If you know a product's SKU, you can typically locate the product online by typing the SKU in the online retailer's search box. If you visit a retail store and have questions about product you saw in an ad, knowing the SKU will help the salesperson find the exact product you are asking about. SKUs are typically listed in small print below the product name and are often preceded by the words "SKU," "Part Number," "Product ID," or something similar.
Skyscraper While not as common as the banner ad, the skyscraper is another prevalent form of Web advertising. Skyscraper ads, which are tall and narrow, get their name from the tall buildings you often see in big cities. They are typically placed to the left or right of the main content on the page, which allows all or part of the ad to be visible even as the user scrolls down the window. Skyscraper ads come in two standard sizes -- 120 pixels wide by 600 pixels high (120x600) and 160 pixels wide by 600 pixels high (160x600). They can contain text advertisements, images, or animations. When users click on a skyscraper ad, they are redirected to the advertiser's website.
Slashdot Press releases can often trigger increased interest in a certain topic, and if a Web site link is provided in the release, this can translate to increased hits to the Web site. If the increase in traffic is so dramatic that it causes the server to be completely unreachable, the server is said to have been "slashdotted." The name came into being after October, 1998, when a press release was published on the Slashdot.org Web site, resulting in a major surge in traffic to another Web server, causing it to go down. You can also use the term as a verb, as in, "Dude, thanks to that stupid article, our server got slashdotted today, man!"
SLI (Scalable Link Interface) Stands for "Scalable Link Interface." SLI is a technology developed by NVIDIA that allows multiple graphics cards to work together in a single computer system. This enables faster graphics performance than what is possible with a single card. For example, using SLI to link two cards together may offer up to twice the performance of a single video card. If each card has two GPUs, the result may be up to four times the performance of a typical video card! For video cards to be linked using NVIDIA's SLI system, the computer must have multiple PCI Express slots. PCI Express is the first video card interface that allows the linking of multiple graphics cards because the slots share the same bus. Previous technologies, such as PCI and AGP, used separate buses, which did not allow graphics cards to be bridged together. The PCI Express slots must also support enough bandwidth for the cards, which typically means they must be x8 or x16 slots. Of course, the cards themselves must also support SLI bridging in order to work together.
SMART (Self-Monitoring Analysis And Reporting Technology) Stands for "Self-Monitoring Analysis And Reporting Technology." It is used to protect and prevent errors in hard drives. The SMART technology basically monitors and analyzes hard drives (hence the name), then checks the health of your hard drive and lets you know if there are any problems. The main purpose of SMART is to keep your hard drive running smoothly and prevent it from crashing.
Smart battery Also known as an intelligent battery, a smart battery is a portable computer battery that has the ability of keeping the computer up-to-date with its power status and other specific battery characteristics.
SMB (Server Message Block) Stands for "Server Message Block." SMB is a network protocol used by Windows-based computers that allows systems within the same network to share files. It allows computers connected to the same network or domain to access files from other local computers as easily as if they were on the computer's local hard drive. Not only does SMB allow computers to share files, but it also enables computers to share printers and even serial ports from other computers within the network. For example, a computer connected to a Windows network could print a document on a printer connected to another computer on the network, as long as both machines support the SMB protocol. Though SMB was originally developed for Windows, it can also be used by other platforms, including Unix and Mac OS X, using a software implementation called Samba. By using Samba instructions, Mac, Windows, and Unix computers can share the same files, folders, and printers. This is great for those Windows-based office networks where there is a graphic designer who refuses to use anything but a Mac and a tech guy who does everything on his Linux machine.
SMS (Short Message Service) Stands for "Short Message Service." SMS is used to send text messages to mobile phones. The messages can typically be up to 160 characters in length, though some services use 5-bit mode, which supports 224 characters. SMS was originally created for phones that use GSM (Global System for Mobile) communication, but now all the major cell phone systems support it. While SMS is most commonly used for text messaging between friends or co-workers, it has several other uses as well. For example, subscription SMS services can transmit weather, news, sports updates, and stock quotes to users' phones. SMS can also notify employees of sales inquiries, service stops, and other information pertinent to their business. Doctors can receive SMS messages regarding patient emergencies. Fortunately, text messages sent via SMS do not require the recipient's phone to be on in order for the message to be successfully transmitted. The SMS service will hold the message until the recipient turns on his or her phone, at which point the message will be be sent to the recipient's phone. Most cell phone companies allow you to send a certain number of text messages every month for no charge. Though it would be a good idea to find out what that number is before you go text message crazy.
SMTP Simple Network Management Protocol. A protocol for client server communication that sends and receives information on top of HTTP.
SMTP (Simple Mail Transfer Protocol) Stands for "Simple Mail Transfer Protocol." This is the protocol used for sending e-mail over the Internet. Your e-mail client (such as Outlook, Eudora, or Mac OS X Mail) uses SMTP to send a message to the mail server, and the mail server uses SMTP to relay that message to the correct receiving mail server. Basically, SMTP is a set of commands that authenticate and direct the transfer of electronic mail. When configuring the settings for your e-mail program, you usually need to set the SMTP server to your local Internet Service Provider's SMTP settings (i.e. "smtp.yourisp.com"). However, the incoming mail server (IMAP or POP3) should be set to your mail account's server (i.e. hotmail.com), which may be different than the SMTP server.
Snapshot While the term "snapshot" is often used in photography, it is also a computing term that refers to a copy made of a disk drive at a specific moment in time. Snapshots are useful for backing up data at different intervals, which allows information to be recovered from different periods of time. A hard drive snapshot includes the full directory structure of a hard disk, including all folders and files on the disk. This type of backup may also be referred to as a "disk image." Disk images allow the full disk to be restored in case the primary disk fails. Many backup programs that create snapshots also allow specific files to be recovered from the snapshot, instead of having to restore the complete backup. Since snapshots are mainly used for backup purposes, it is wise to save the snapshot to a secondary hard drive, removable drive, or optical media, such as CDs or DVDs.
SNMP (Simple Network Management Protocol) Stands for "Simple Network Management Protocol." SNMP is used for exchanging management information between network devices. For example, SNMP may be used to configure a router or simply check its status. There are four types of SNMP commands used to control and monitor managed devices: 1) read, 2) write, 3) trap, and 4) traversal operations. The read command is used to monitor devices, while the write command is used to configure devices and change device settings. The trap command is used to "trap" events from the device and report them back to the monitoring system. Traversal operations are used to determine what variables a certain device supports. SNMP has no authentication capabilities, which means it is not a very secure protocol. For this reason, SNMP is often used for monitoring networks rather than managing them. So, practically speaking, SNMP could be considered as a "Simple Network Monitoring Protocol" instead.
SOA (Service Oriented Architecture) Stands for "Service Oriented Architecture." When businesses grow, they often add new products and services. While these additions may help make the business larger, it is often difficult to implement them in an efficient manner. The goal of SOA is to make it easy for businesses to grow and add new services. The Service Oriented Architecture is based on components that work seamlessly with each other. For example, a company sells clothing through an online store. After a few months of successful sales, the company decides to add a jewelry department. An SOA component conveniently adds a new section to the store, in this case, specifically for jewelry. The company then wants to add new shipping options. A SOA shipping component makes adding the new shipping options as easy as checking a few boxes in an administrative control panel. Initially, the company only offered e-mail support, but later decides that adding phone support would be beneficial. A phone support component allows the phone representatives to look up customer orders the same way the e-mail support specialists could. Basically, SOA makes it possible for a business to add new features and services without having to create them from scratch. Instead, they can be added or modified as needed, making it simple and efficient to expand the business. Because many products and services are now offered via the Web, most SOA solutions include Web-based implementations.
SOAP (Simple Object Access Protocol) Stands for "Simple Object Access Protocol," and can do more than just get your hands clean. SOAP is a method of transferring messages, or small amounts of information, over the Internet. SOAP messages are formatted in XML and are typically sent using HTTP (hypertext transfer protocol). Both are widely supported data transmission standards. HTTP, which is the protocol that Web pages are sent over, has the additional advantage of avoiding most network firewalls. Since firewalls usually do not block port 80 (HTTP) traffic, most SOAP messages can pass through without any problems. Each SOAP message is contained in an "envelope" that includes a header and a body. The header may include the message ID and date the message was sent, while the body contains the actual message. Because SOAP messages all use the same format, they are compatible with many different operating systems and protocols. For example, a user can send a SOAP message from a Windows XP machine to a Unix-based Web server without worrying about the message being altered. The Unix machine can then redirect the message to the appropriate location or open the file using a program on the system. While most SOAP messages are sent over the Web via HTTP, they can also be sent via e-mail, using SMTP.
Social Networking When the Web became popular in the mid-1990s, it enabled people to share information in ways that were never possible before. But as limitless as the possibilities seemed, there was a personal aspect that was lacking. While users could create home pages and post their own content on the Web, these individual sites lacked a sense of community. In the early 2000s, the Web became much more personal as social networking websites were introduced and embraced by the masses. Social networking websites allow users to be part of a virtual community. The two most popular sites are currently Facebook and MySpace. These websites provide users with simple tools to create a custom profile with text and pictures. A typical profile includes basic information about the user, at least one photo, and possibly a blog or other comments published by the user. Advanced profiles may include videos, photo albums, online applications (in Facebook), or custom layouts (in MySpace). After creating a profile, users can add friends, send messages to other users, and leave comments directly on friends' profiles. These features provide the building blocks for creating online communities. Thanks to social networking websites, users can share their lives with other people without needing to develop and publish their own home pages. These websites also provide an important linking element between users that allows friends to communicate directly with each other. Because people often have friends from different places and different times in their lives, social networking sites provide an opportunity to keep in touch with old friends and to meet new people as well. Of course, this means that people you don't know may also be able to view your profile page. Therefore, if you join a social networking website, it is a good idea to review the privacy settings for your account. And more importantly, remember to always use discretion in what you publish on your profile.
Socket When a computer program needs to connect to a local or wide area network such as the Internet, it uses a software component called a socket. The socket opens the network connection for the program, allowing data to be read and written over the network. It is important to note that these sockets are software, not hardware, like a wall socket. So, yes, you have a much greater chance of being shocked by a wall socket than by a networking socket. Sockets are a key part of Unix and Windows-based operating systems. They make it easy for software developers to create network-enabled programs. Instead of constructing network connections from scratch for each program they write, developers can just include sockets in their programs. The sockets allow the programs to use the operating system's built-in commands to handle networking functions. Because they are used for a number of different network protocols (i.e. HTTP, FTP, telnet, and e-mail), many sockets can be open at one time.
SO-DIMM (Small Outline Dual In-Line Memory Module) Stands for "Small Outline Dual In-Line Memory Module." Most desktop computers have plenty of space for RAM chips, so the size of the memory modules is not a concern. However, with laptops, the size of the memory modules matters significantly. Because laptops are designed to be as small and as light as possible, the size of each component matters. In fact, laptop parts are so crammed together, large RAM chips often do not fit into the overall laptop design. This is why SO-DIMMs were created. A SO-DIMM is about half the length of a regular size DIMM. This allows greater flexibility in designing the memory slots for laptops. Many laptops have a user-accessible section that houses the SO-DIMMs, which make it easy to upgrade the computer's RAM. If the RAM chips were full size DIMMs, this type of design would be harder to incorporate and would likely increase the size of the laptop. The first SO-DIMMs used 72 pins (or connectors) and supported 32-bit data transfers. Modern SO-DIMMs, however, typically use 144 pins, which allows for the same 64-bit transfers that a regular size DIMM does. While SO-DIMMs are used primarily in laptops, some desktop computers with small form factors also use SO-DIMMs to reduce the overall size of the case. However, when size is not an issue, regular DIMMs are typically used because they are a more cost-effective solution.
Soft Copy A soft copy is a document saved on a computer. It is the electronic version of a document, which can be opened and edited using a software program. The term "soft copy" is most often used in contrast to hard copy, which is the printed version of a document. Soft copies can be sent via e-mail or over a network connection, which makes them a more efficient and cost effective option than using hard copies for communications. The downside to using soft copies is that they require a computer and software to open and can be accidentally deleted. Of course, some people have so many papers on their desks, a soft copy may be less likely to disappear.
Soft Token A soft token is a software version of a hard token, which is a security device used to give authorized users access to secure locations or computer systems. For this reason, soft tokens can be called "virtual tokens," since they are a virtual version of hardware keys and other physical security devices. Soft tokens are typically generated by a central server that runs security software. They are sent to users' devices, such as cell phones, PDAs, and laptops. Once the soft token has been received by the device, the user can use the device within a secure network or can gain access to the sever as an authorized user. To add an extra measure of security, most soft token authentication also requires a username and password to make sure the correct user is using the authorized device.
Software Computer software is a general term that describes computer programs. Related terms such as software programs, applications, scripts, and instruction sets all fall under the category of computer software. Therefore, installing new programs or applications on your computer is synonymous with installing new software on your computer. Software can be difficult to describe because it is "virtual," or not physical like computer hardware. Instead, software consists of lines of code written by computer programmers that have been compiled into a computer program. Software programs are stored as binary data that is copied to a computer's hard drive, when it is installed. Since software is virtual and does not take up any physical space, it is much easier (and often cheaper) to upgrade than computer hardware. While at its most basic level, software consists of binary data, CD-ROMs, DVDs, and other types of media that are used to distribute software can also be called software. Therefore, when you buy a software program, it often comes on a disc, which is a physical means of storing the software.
Solid State Solid state, at its most basic level, means "no moving parts." Therefore, solid state electronic devices are made up of solid components that do not move. Some examples include computer motherboards and integrated circuits. Devices that use only solid state parts, such as television sets, speakers, and digital watches, are often referred to as solid state products. Flash memory devices are solid state products, while hard drives are not. This is because hard drives use a spinning disk and moving drive head to read and write data, while flash memory uses electric charges to perform the same functions. For this reason, flash memory devices are seen as more durable than hard drives. This is why flash memory is often used in products such as portable MP3 players and digital cameras. Because solid state devices have no moving parts, they are less likely to break down than devices that have mobile mechanisms. For this reason, it is often more worthwhile to buy an extended warranty on electronics that have moving parts than those that do not. That is something you may want to think about next time you are shopping.
Sound Card The sound card is a component inside the computer that provides audio input and output capabilities. Most sound cards have at least one analog line input and one stereo line output connection. The connectors are typically 3.5 mm minijacks, which are the size most headphones use. Some sound cards also support digital audio input and output, either through a standard TRS (tip-ring-sleeve) connection or via an optical audio port, such as Toslink connector. While there are many types of sound cards, any type that produces an analog output must include a digital-to-analog converter (DAC). This converts the outgoing signal from digital to analog, which can be played through most speaker systems. Sounds cards that support analog input also require an analog-to-digital converter (ADC). This digitizes the incoming analog signal, so the computer can process it. In some computers, the sound card is part of the motherboard, while other machines may have an actual card that reside in a PCI slot. If you want to more audio capabilities to your computer, such as additional input or output channels, you can install a new sound card. Professional sound cards often support higher sampling rates (such as 192 kHz instead of 44.1 kHz) and may have more inputs and outputs. Some cards may also have 1/4 in. connectors instead of 3.5 mm, which accommodates most instrument outputs. While professional sound cards can add more audio capabilities to your computer, another popular option for multi-channel recording is a breakout box. This is an external box that typically includes a built-in sound card and multiple audio connections. For example, a breakout box may support 16 channels of audio, which would be impossible to fit on a single card. Most breakout boxes connect to a Firewire or USB port, though some connect to a sound card specifically designed to communicate with the box.
Source Code Every computer program is written in a programming language, such as Java, (C/C++|cplusplus), or Perl. These programs include anywhere from a few lines to millions of lines of text, called source code. Source code, often referred to as simply the "source" of a program, contains variable declarations, instructions, functions, loops, and other statements that tell the program how to function. Programmers may also add comments to their source code that explain sections of the code. These comments help other programmers gain at least some idea of what the source code does without requiring hours to decipher it. Comments can be helpful to the original programmer as well if many months or years have gone by since the code was written. Short programs called scripts can be run directly from the source code using a scripting engine, such as a VBScript or PHP engine. Most large programs, however, require that the source code first be compiled, which translates the code into a language the computer can understand. When changes are made to the source code of these programs, they must be recomplied in order for the changes to take effect in the program. Small programs may use only one source code file, while larger programs may reference hundreds or even thousands of files. Having multiple source files helps organize the program into different sections. Having one file that contains every variable and function can make it difficult to locate specific sections of the code. Regardless of how many source code files are used to create a program, you will most likely not see any of the original files on your computer. This is because they are all combined into one program file, or application, when they are compiled.
Southbridge The southbridge is a chip that connects the northbridge to other components inside the computer, including hard drives, network connections, USB and Firewire devices, the system clock, and standard PCI cards. The southbridge sends and receives data from the CPU through the northbridge chip, which is connected directly to the computer's processor. Since the southbridge is not connected directly to the CPU, it does not have to run as fast as the northbridge chip. However, it processes data from more components, so it must be able to multitask well. On Intel systems, the southbridge is also referred to as the I/O Controller Hub, since it controls the input and output devices.
Spam Originating from the name of Hormel's canned meat, "spam" now also refers to junk e-mail or irrelevant postings to a newsgroup or bulletin board. The unsolicited e-mail messages you receive about refinancing your home, reversing aging, and losing those extra pounds are all considered to be spam. Spamming other people is definitely not cool and is one of the most notorious violations of Internet etiquette (or "netiquette"). So if you ever get the urge to let thousands of people know about that hot new guaranteed way to make money on the Internet, please reconsider.
SpeedStep A feature available with Intel Pentium III, Pentium III-Mobile, Pentium 4-Mobile, and later Intel mobile processors that allows a user to control features of the processor through software that lower its speed. By reducing the overall speed of the processor it helps conserve power and reduce the heat produced by the processor, which saves on battery life. If your looking for software and/or drivers relating to SpeedStep for your computer running versions of Microsoft Windows 2000 or earlier you must contact the computer manufacturer. Intel does not provide any software for this feature.
Spider A spider is a software program that travels the Web (hence the name "spider"), locating and indexing websites for search engines. All the major search engines, such as Google and Yahoo!, use spiders to build and update their indexes. These programs constantly browse the Web, traveling from one hyperlink to another. For example, when a spider visits a website's home page, there may be 30 links on the page. The spider will follow each of the links, adding all the pages it finds to the search engine's index. Of course, the new pages that the spider finds may also have links, which the spider continues to follow. Some of these links may point to pages within the same website (internal links), while others may lead to different sites (external links). The external links will cause the spider to jump to new sites, indexing even more pages. Because of the interwoven nature of website links, spiders often return to websites that have already been indexed. This allows search engines to keep track of how many external pages link to each page. Usually, the more incoming links a page has, the higher it will be ranked in search engine results. Spiders not only find new pages and keep track of links, they also track changes to each page, helping search engine indexes stay up to date. Spiders are also called robots and crawlers, which may be preferable for those who are not fond of arachnids. The word "spider" can also be used as verb, such as, "That search engine finally spidered my website last week."
Spoofing The word "spoof" means to hoax, trick, or deceive. Therefore, in the IT world, spoofing refers tricking or deceiving computer systems or other computer users. This is typically done by hiding one's identity or faking the identity of another user on the Internet. Spoofing can take place on the Internet in several different ways. One common method is through e-mail. E-mail spoofing involves sending messages from a bogus e-mail address or faking the e-mail address of another user. Fortunately, most e-mail servers have security features that prevent unauthorized users from sending messages. However, spammers often send spam messages from their own SMTP, which allows them to use fake e-mail addresses. Therefore, it is possible to receive e-mail from an address that is not the actual address of the person sending the message. Another way spoofing takes place on the Internet is via IP spoofing. This involves masking the IP address of a certain computer system. By hiding or faking a computer's IP address, it is difficult for other systems to determine where the computer is transmitting data from. Because IP spoofing makes it difficult to track the source of a transmission, it is often used in denial-of-service attacks that overload a server. This may cause the server to either crash or become unresponsive to legitimate requests. Fortunately, software security systems have been developed that can identify denial-of-service attacks and block their transmissions. Finally, spoofing can be done by simply faking an identity, such as an online username. For example, when posting on an Web discussion board, a user may pretend he is the representative for a certain company, when he actually has no association with the organization. In online chat rooms, users may fake their age, gender, and location. While the Internet is a great place to communicate with others, it can also be an easy place to fake an identity. Therefore, always make sure you know who you are communicating with before giving out private information.
Spreadsheet A spreadsheet is a document that stores data in a grid of rows and columns. Rows are typically labeled using numbers (1, 2, 3, etc.), while columns are labeled with letters (A, B, C, etc). Individual row/column locations, such as C3 or B12, are referred to as cells. Each cell can each store a unique instance of data. By entering data into a spreadsheet, information can be stored in a more structured way than using plain text The row/column structure also allows the data to be analyzed using formulas and calculations. For example, each row of a spreadsheet may store information about a person who has an account with a certain company. Each column may store a different aspect of the person's information, such as the first name, last name, address, phone number, favorite food, etc. The spreadsheet program can analyze this data by counting the number of people who live in a certain zip code, listing all the people who's favorite food is fried veal, or performing other calcuations. In this way, a spreadsheet is similar to a database. However, spreadsheets are more streamlined than databases and are especially useful for processing numbers. This is why spreadsheets are commonly used in scientific and financial applications. For example, a spreadsheet may store bank account data, including balance and interest information. A column that stores the account balances of several clients can easily be summed to produce the total value of all the clients' balances. These amounts can be multiplied by the interest rate from another cell to see what the value of the accounts will be in a year. Once the formula has been created, modifying the value of just the interest rate cell will also change the projected value of all the accounts. The most commonly used spreadsheet application is Microsoft Excel, but several other spreadsheet programs are available including IBM Lotus 1-2-3 for Windows and AppleWorks and Numbers for Mac OS X.
Spyware As the name implies, this is software that "spies" on your computer. Nobody likes to be spied on, and your computer doesn't like it either. Spyware can capture information like Web browsing habits, e-mail messages, usernames and passwords, and credit card information. If left unchecked, the software can transmit this data to another person's computer over the Internet. So how does spyware get on your computer? Just like viruses, spyware can be installed when you open an e-mail attachment containing the malicious software. It can also be installed when you install another program that has a spyware installer attached to it. Because of the insidious nature of spyware, most people don't even know when spyware is on their computer. Fortunately, you can purchase anti-spyware utilities that will search for spyware on your computer and stomp the unwanted software out of your system. A good way to prevent spyware from infecting your computer is to install a security program that lets you know when any program is being installed, so that you can choose to authorize or stop the installation.
SQL (Structured Query Language) Stands for "Structured Query Language," and can be pronounced as either "sequel" or "S-Q-L." It is a query language used for accessing and modifying information in a database. Some common SQL commands include "insert," "update," and "delete." The language was first created by IBM in 1975 and was called SEQUEL for "Structured English Query Language." Since then, it has undergone a number of changes, many coming from Oracle products. Today, SQL is commonly used for Web database development and management. Though SQL is now considered to be a standard language, there are still a number of variations of it, such as mSQL and mySQL. By using a scripting language like PHP, SQL commands can be executed when a Web page loads. This makes it possible to create dynamic Web pages that can display different information each time they load.
SRAM Static random access memory. Faster and more expensive than DRAM.
SRAM (Static Random Access Memory) Stands for "Static Random Access Memory." I know it is tempting to pronounce this term as "Sram," but it is correctly pronounced "S-ram." SRAM is a type of RAM that stores data using a static method, in which the data remains constant as long as electric power is supplied to the memory chip. This is different than DRAM (dynamic RAM), which stores data dynamically and constantly needs to refresh the data stored in the memory. Because SRAM stores data statically, it is faster and requires less power than DRAM. However, SRAM is more expensive to manufacture than DRAM because it is built using a more complex structure. This complexity also limits the amount of data a single chip can store, meaning SRAM chips cannot hold as much data as DRAM chips. For this reason, DRAM is most often used as the main memory for personal computers. However, SRAM is commonly used in smaller applications, such as CPU cache memory and hard drive buffers. It is also used in other consumer electronics, from large appliances to small children's toys. It is important to not confuse SRAM with SDRAM, which is a type of DRAM.
sRGB (Standard Red Green Blue) Stands for "Standard RGB" (and RGB stands for Red-Green-Blue"). All the colors you see on your computer display are made up various mixtures of red, green, and blue light. While this works great for individual displays, the same colors are often displayed differently on different screens. For example, dark red on one screen may look like red-orange on another. When you add printers, scanners, and digital cameras to the mix, the problem is magnified even more. To help achieve a greater color consistency between hardware devices, the sRGB standard was created in 1999. It defines a gamut of colors that represents each color well and can be used by CRT monitors, LCD screens, scanners, printers, and digital cameras. It also has been incorporated into many Web browsers to make sure the colors on Web pages match the color scheme of the operating system. Because of the color consistency sRGB creates, most hardware devices that work with images now use it as the default setting.
SSH (Secure Shell) Stands for "Secure Shell." SSH is a method of securely communicating with another computer. The "secure" part of the name means that all data sent via an SSH connection is encrypted. This means if a third party tries to intercept the information being transferred, it would appear scrambled and unreadable. The "shell" part of the name means SSH is based on a Unix shell, which is a program that interprets commands entered by a user. Because SSH is based on a Unix shell, standard Unix commands can be used to view, modify, and transfer files from a remote machine once an SSH connection has been established. These commands can either be entered manually using a terminal emulator, or may be sent from a program with a graphical user interface (GUI). This type of program translates user actions, such as opening a folder, to Unix commands (cd [folder name]). To log into a server using SSH from a terminal program, type: ssh [servername] -l [username]. The "-l" indicates you are logging in with a username, which is required by most SSH connections (otherwise, it wouldn't be very secure). If the login name is recognized, you will be prompted to enter a password. If the password is correct, your SSH connection will be established. To end the SSH session, type "exit" followed by the Enter key.
SSID (Service Set Identifier) Stands for "Service Set Identifier." An SSID is a unique ID that consists of 32 characters and is used for naming wireless networks. When multiple wireless networks overlap in a certain location, SSIDs make sure that data gets sent to the correct destination. The SSID is different than the name that is assigned to a wireless router. For example, the administrator of a wireless network may set the name of the router, or base station, to "Office." This will be the name that users see when browsing available wireless networks, but the SSID is a different 32 character string that ensures the network name is different from other nearby networks. Each packet sent over a wireless network includes the SSID, which ensures that the data being sent over the air arrives at the correct location. Without service set identifiers, sending and receiving data in a location with multiple wireless networks would be chaotic and unpredictable to say the least.
SSL (Secure Sockets Layer) Stands for "Secure Sockets Layer." SSL is a secure protocol developed for sending information securely over the Internet. Many websites use SSL for secure areas of their sites, such as user account pages and online checkout. Usually, when you are asked to "log in" on a website, the resulting page is secured by SSL. SSL encrypts the data being transmitted so that a third party cannot "eavesdrop" on the transmission and view the data being transmitted. Only the user's computer and the secure server are able to recognize the data. SSL keeps your name, address, and credit card information between you and merchant to which you are providing it. Without this kind of encryption, online shopping would be far too insecure to be practical. When you visit a Web address starting with "https," the "s" after the "http" indicates the website is secure. These websites often use SSL certificates to verify their authenticity. While SSL is most commonly seen on the Web (HTTP), it is also used to secure other Internet protocols, such as SMTP for sending e-mail and NNTP for newsgroups. Early implementations of SSL were limited to 40-bit encryption, but now most SSL secured protocols use 128-bit encryption or higher.
Stack A stack is a type of data structure -- a means of storing information in a computer. When a new object is entered in a stack, it is placed on top of all the previously entered objects. In other words, the stack data structure is just like a stack of cards, papers, credit card mailings, or any other real-world objects you can think of. When removing an object from a stack, the one on top gets removed first. This method is referred to as LIFO (last in, first out). The term "stack" can also be short for a network protocol stack. In networking, connections between computers are made through a series of smaller connections. These connections, or layers, act like the stack data structure, in that they are built and disposed of in the same way.
Standalone A standalone device is able to function independently of other hardware. This means it is not integrated into another device. For example, a TiVo box that can record television programs is a standalone device, while a DVR that is integrated into a digital cable box is not standalone. Integrated devices are typically less expensive than multiple standalone products that perform the same functions. However, using standalone hardware typically allows the user greater customization, whether it be a home theater or computer system. Standalone can also refer to a software program that does not require any software other than the operating system to run. This means that most software programs are standalone programs. Software such as plug-ins and expansion packs for video games are not standalone programs since they will not run unless a certain program is already installed.
Standby When electronic devices are receiving power but are not running, they are in standby mode. For example, a television is in standby mode when it is plugged in, but turned off. While the TV is not "on," it is ready to receive a signal from the remote control. An A/V receiver is also in standby mode when it is plugged in and turned off. This is because the receiver may be activated by receiving input from a connected device or by being turned on directly with the remote control. In other words, these devices are "standing by," waiting to receive input from the user or another device. When a computer is in standby mode, it is not completely turned off. Instead, it has already been turned on, but has gone into "sleep" mode. Therefore, when referring to computers, "Sleep" and "Standby" may be used synonymously. A computer in standby mode requires a small amount of current, called a "trickle charge," that keeps the current state of running software saved in the computer's RAM. However, because the computer is in sleep mode, the CPU, video card, and hard drive are not running. Therefore, the computer uses very little power in standby mode. Since standby mode saves energy, it is a good idea to put your computer to sleep if you are going to be away from it for more than 15 or 20 minutes. You can also use the Power Options control panel (in Windows) or the Energy Saver System Preference (in Mac OS X) to automatically put your computer to sleep after it has been inactive for a specific amount of time. Then, when you take a break from your computer, your computer can take a break as well.
Status Bar A status bar is a small area at the bottom of a window. It is used by some applications to display helpful information for the user. For example, an open folder window on the desktop may display the number of items in the folder and how many items are selected. Photoshop uses the status bar to display the size of the current image, the zoom percentage, and other information. Web browsers use the status bar to display the Web address of a link when the user moves the cursor over it. It also shows the status of loading pages, and displays error messages. If you don't see the status bar in your Web browser or another program, you may be able to enable it by selecting "Show Status Bar" from the application's View menu. If this option is not available in the View menu, the program may not use a status bar. Some programs use a "status window" instead to show the current activity in the application. The option for displaying this window is usually found in the "Window" menu.
Storage Device A computer storage device is any type of hardware that stores data. The most common type of storage device, which nearly all computers have, is a hard drive. The computer's primary hard drive stores the operating system, applications, and files and folders for users of the computer. While the hard drive is the most ubiquitous of all storage devices, several other types are common as well. Flash memory devices, such as USB keychain drives and iPod nanos are popular ways to store data in a small, mobile format. Other types of flash memory, such as compact flash and SD cards are popular ways to store images taken by digital cameras. External hard drives that connect via Firewire and USB are also common. These types of drives are often used for backing up internal hard drives, storing video or photo libraries, or for simply adding extra storage. Finally, tape drives, which use reels of tape to store data, are another type of storage device and are typically used for backing up data.
Streaming Data streaming, commonly seen in the forms of audio and video streaming, is when a multimedia file can be played back without being completely downloaded first. Most files, like shareware and software updates that you download off the Internet, are not streaming data. However, certain audio and video files like Real Audio and QuickTime documents can be streaming files, meaning you can watch a video or listen to a sound file while it's being downloaded to your computer. With a fast Internet connection, you can actually stream live audio or video to your computer.
String A string is a data type used in programming, such as an integer and floating point unit, but is used to represent text rather than numbers. It is comprised of a set of characters that can also contain spaces and numbers. For example, the word "hamburger" and the phrase "I ate 3 hamburgers" are both strings. Even "12345" could be considered a string, if specified correctly. Typically, programmers must enclose strings in quotation marks for the data to recognized as a string and not a number or variable name. For example, in the comparison: if (Option1 == Option2) then ... Option1 and Option2 may be variables containing integers, strings, or other data. If the values are the same, the test returns a value of true, otherwise the result is false. In the comparison: if ("Option1" == "Option2") then ... Option1 and Option2 are being treated as strings. Therefore the test is comparing the words "Option1" and "Option2," which would return false. The length of a string is often determined by using a null character.
Subnet Mask A subnet mask is a number that defines a range of IP addresses that can be used in a network. (It is not something you wear on your head to keep subnets out.) Subnet masks are used to designate subnetworks, or subnets, which are typically local networks LANs that are connected to the Internet. Systems within the same subnet can communicate directly with each other, while systems on different subnets must communicate through a router. Therefore, subnetworks can be used to partition multiple networks and limit the traffic between them. A subnet mask hides, or "masks," the network part of a system's IP address and leaves only the host part as the machine identifier. A common subnet mask for a Class C IP address is 255.255.255.0. Each section of the subnet mask can contain a number from 0 to 256, just like an IP address. Therefore, in the example above, the first three sections are full, meaning the IP addresses of computers within the subnet mask must be identical in the first three sections. The last section of each computer's IP address can be anything from 0 to 255. For example, the IP addresses 10.0.1.201 and 10.0.1.202 would be in the same subnet, while 10.0.2.201 would not. Therefore, a subnet mask of 255.255.255.0 allows for close to 256 unique hosts within the network (since not all 256 IP addresses can be used). If your system is connected to a network, you can typically view the network's subnet mask number in the Network control panel (Windows) or System Preference (Mac OS X). Most home networks use the default subnet mask of 255.255.255.0. However, some office networks may use a different subnet mask such as 255.255.255.128, which can be used to split a network into two subnets. Large networks with several thousand machines may use a subnet mask of 255.255.0.0. This is the default subnet mask used by Class B networks. The largest Class A networks use a default subnet mask of 255.0.0.0.
Superscalar A superscalar CPU can execute more than one instruction per clock cycle. Because processing speeds are measured in clock cycles per second (megahertz), a superscalar processor will be faster than a scalar processor rated at the same megahertz. A superscalar architecture includes parallel execution units, which can execute instructions simultaneously. This parallel architecture was first implemented in RISC processors, which use short and simple instructions to perform calculations. Because of their superscalar capabilities, RISC processors have typically performed better than CISC processors running at the same megahertz. However, most CISC-based processors (such as the Intel Pentium) now include some RISC architecture as well, which enables them to execute instructions in parallel. Nearly all processors developed after 1998 are superscalar.
Surge Protector The surge protector is an important, yet often overlooked part of a computer setup. It allows multiple devices to plugged in to it at one time and protects each connected device from power surges. For example, a home office may have a computer, monitor, printer, cable modem, and powered speakers all plugged into one surge protector, which is plugged into a single outlet in the wall. The surge protector allows many devices to use one outlet, while protecting each of them from electrical surges. Surge protectors, sometimes called power strips, prevent surges in electrical current by sending the excess current to the grounding wire (which is the round part of the plug below the two flat metal pieces on U.S. outlet plugs). If the surge is extra high, such as from a lightning strike, a fuse in the surge protector will blow and the current will prevented from reaching any of the devices plugged into the surge protector. This means the noble surge protector will have given its life for the rest of the equipment, since the fuse is destroyed in the process. While surge protectors all perform the same basic function, they come in many shapes and sizes with different levels of protection. Some may look like basic power strips, while others may be rack mounted or fit directly against the wall. Most surge protectors offer six to ten different outlets. Cheaper surge protectors offer limited protection for surges (under 1000 joules), while more expensive ones offer protection for several thousand joules and include a monetary guarantee on connected devices if a power surge happens. Typically, you get what you pay for, so if you have an expensive computer system, it is wise to buy a quality surge protector that offers at least 1000 joules of protection. Some surge protectors also include line conditioning, which uses an electromagnet to maintain a consistent level of electricity when there are slight variations in current. For example, you might notice your computer monitor or television fade for a moment when you turn on a high-powered device, like a vacuum or air conditioner. A surge protector with line conditioning should prevent connected devices from being affected by these slight variances in current. While you may be able to hook up your computer system without a surge protector, it is important to protect your equipment by using one. You may not need a large, expensive surge protector with line conditioning, but using a quality surge protector for all your electronic devices is a smart choice.
Switch A switch is used to network multiple computers together. Switches made for the consumer market are typically small, flat boxes with 4 to 8 Ethernet ports. These ports can connect to computers, cable or DSL modems, and other switches. High-end switches can have more than 50 ports and often are rack mounted. Switches are more advanced than hubs and less capable than routers. Unlike hubs, switches can limit the traffic to and from each port so that each device connected to the switch has a sufficient amount of bandwidth. For this reason, you can think of a switch as a "smart hub." However, switches don't provide the firewall and logging capabilities that routers do. Routers can often be configured by software (typically via a Web interface), while switches only work the way the hardware was designed. The term "switch" can also be used to refer to a small lever or button on computer hardware. And while it has nothing to do with computers, "riding switch" means riding backwards in skateboarding and snowboarding.
Syntax Each spoken language has a general set of rules for how words and sentences should be structured. These rules are collectively known as the language syntax. In computer programming languages, syntax serves the same purpose, defining how declarations, functions, commands, and other statements should be arranged. Each computer programming language uses a different syntax. Many languages share similar syntax rules, while others have a very unique syntax design. For example, C and Java use a highly similar syntax, while Perl has many characteristics that are not seen in either the C or Java languages. Regardless of the rules, a program's source code must have the correct syntax in order to compile correctly and be made into a program. In fact, it must have the exact right syntax, or the program will fail to compile and produce a "syntax error." A syntax error can be as simple as a missing parenthesis or a forgotten semicolon at the end of a statement. Even these small errors will keep the source code from compiling. Fortunately, most software development programs include a debugger, which helps find the exact location of syntax errors within the source code. Imagine a program that has over ten thousand lines of code and a syntax error is caused by one missing semicolon. Finding a needle in a haystack would be preferred over manually locating the error. Needless to say, the debugger makes the debugging process much easier for the programmer.
System Analyst A system analyst is the person who selects and configures computer systems for an organization or business. His or her job typically begins with determining the intended purpose of the computers. This means the analyst must understand the general objectives of the business, as well as what each individual user's job requires. Once the system analyst has determined the general and specific needs of the business, he can choose appropriate systems that will help accomplish the goals of the business. When configuring computer systems for a business, the analyst must select both hardware and software. The hardware aspect includes customizing each computer's configuration, such as the processor speed, amount of RAM, hard drive space, video card, and monitor size. It may also involve choosing networking equipment that will link the computers together. The software side includes the operating system and applications that are installed on each system. The software programs each person requires may differ greatly between users, which is why it is important that the system analyst knows the specific needs of each user. To summarize, the system analyst's job is to choose the most efficient computer solutions for a business, while making sure the systems meet all the company's needs. Therefore, the system analyst must have a solid understanding of computer hardware and software and should keep up-to-date on all the latest technologies. He must also be willing to listen to the constant needs and complaints of the users he builds systems for.
System Hardening Most computers offer network security features to limit outside access to the system. Software such as antivirus programs and spyware blockers prevent malicious software from running on the machine. Yet, even with these security measures in place, computers are often still vulnerable to outside access. System hardening, also called Operating System hardening, helps minimize these security vulnerabilities. The purpose of system hardening is to eliminate as many security risks as possible. This is typically done by removing all non-essential software programs and utilities from the computer. While these programs may offer useful features to the user, if they provide "back-door" access to the system, they must be removed during system hardening. Advanced system hardening may involve reformatting the hard disk and only installing the bare necessities that the computer needs to function. The CD drive is listed as the first boot device, which enables the computer to start from a CD or DVD if needed. File and print sharing are turned off if not absolutely necessary and TCP/IP is often the only protocol installed. The guest account is disabled, the administrator account is renamed, and secure passwords are created for all user logins. Auditing is enabled to monitor unauthorized access attempts. While these steps are often part of operating system hardening, system administrators may choose to perform other tasks that boost system security. While both Macintosh and Windows operating systems can be hardened, system hardening is more often done on Windows machines, since they are more likely to have their security compromised.
System Requirements Whenever you purchase software or hardware for your computer, you should first make sure your computer supports the system requirements. These are the necessary specifications your computer must have in order to use the software or hardware. For example, a computer game may require you computer to have Windows XP or later, a 2.0 GHz processor, 512 MB or RAM, a 64 MB graphics card, and 500 MB or hard drive space. If your computer does not meet all of these requirements, the game will not run very well or might not run at all. It is just as important to check system requirements for hardware devices. For example, if you buy a printer, it may require either Windows XP or Mac OS X 10.3 or later. It may also require a USB port and 80 MB of available hard drive space. If your computer does not have any USB ports, you will not be able to physically connect the printer. If your machine does not have Windows XP or Mac OS X 10.3 or later, the printer drivers may be incompatible with your operating system. This means you computer will be unable to recognize the printer. Most hardware and software products have the system requirements printed on the side or bottom of the product packaging. When you are shopping for computer software or hardware, it is a good idea to first find out exactly what your system's specifications are and write them down on a piece of paper.
System Resources Your computer has many types of resources. They include the CPU, video card, hard drive, and memory. In most cases, the term "system resources" is used to refer to how much memory, or RAM, your computer has available. For example, if you have 1.0 GB (1024 MB) of RAM installed on your machine, then you have a total of 1024 MB of system resources. However, as soon as your computer boots up, it loads the operating system into the RAM. This means some of your computer's resources are always being used by the operating system. Other programs and utilities that are running on your machine also use your computer's memory. If your operating system uses 300 MB of RAM and your active programs are using 200 MB, then you would have 524 MB of "available system resources." To increase your available system resources, you can close active programs or increase your total system resources by adding more RAM. System resources can also refer to what software is installed on your machine. This includes the programs, utilities, fonts, updates, and other software that is installed on your hard drive. For example, if a file installed with a certain program is accidentally removed, the program may fail to open. The error message may read, "The program could not be opened because the necessary resources were not found." As you can see, the term "system resources" can be a bit ambiguous. Just remember that while it usually refers to your computer's memory, it can be used to describe other hardware or software as well.
System Unit This is the technical term that refers to the box that houses your computer. The system unit refers to the computer itself but does not include the monitor, the keyboard, the mouse, or any other peripherals. I suppose most people will probably know what you mean when you refer to "the box," but saying "system unit" will definitely make you sound more sophisticated.
Systray The systray, short for "system tray," is located on the right side of the Windows toolbar. It is the collection of small icons on the opposite side of the Start Menu. The volume control and the date & time are default items in the systray and many more can be added. Some common icons that get placed in the systray are virus-scan, mouse, and instant messenger icons. They usually get put in the systray (whether you like it or not) when their respective programs are installed. The nice thing about the systray is that it allows quick and easy access to programs and control settings. Most systray icons will open a control panel or program when double-clicked. However, if you install too many of them, the area can get so cluttered, you may find it easier to just browse your hard drive and open the program.

 

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