Name Description
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. 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.
Sampling: Measurement in discrete, regular intervals. Spatial sampling in a digital camera is done by the number of pixels in a given sized area sensor. Tonal sampling is determined by the bit-depth of the analog to digital converter. Correct spatial sampling in high-resolution astrophotography matches the sample size (pixel size) to the size of the Airy disk and seeing, based on the Nyquist sampling theorem.
SATA: 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
Saturation: 1.) Tonal or pixel values on the bright end of the dynamic range that are maxed out and contain no detail.
2.) The purity or vividness of a color.
Scaling: 1.) Changing the black or white endpoints in image histogram to modify the data so that it changes its distribution in the dynamic range.
2.) Enlarging or reducing the size of an image.
Scanner: A scanner is an input device that scans documents and images, which can be imported into a computer. They are available in flatbed or sheet-fed versions and are usually connected via a high-speed USB port. OCR software can be used to recognize text documents imported from a scanner.
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.
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.
Scroll Wheel: 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.
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.
SD: 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-right corner of each SD card is slanted.
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. 
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.
Short Circuit The condition caused when a current flow is interrupted short of or before reaching the device terminating the cable. A short circuit is caused when a hot conductor comes into contact with neutral or ground conductors.
Single Band IR: Single band extenders only work in the first band. This works for almost all DVD and blu ray players.
Smartphone: A smartphone combines standard mobile phone features with advanced features found on personal device assistants (PDAs). Most smartphones include e-mail and Web surfing capabilities, as well as the ability to display photos, and play music and video files.

Smartphones have advanced system software, much like a computer operating system, which allows them to perform multiple functions. Many smartphones now support third-party applications or "apps," which users can install on the phone.
SMTP 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, Live, or Gmail) 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.
Spam: Spam 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.
Speakers: Speakers are popular output devices used with computer systems. They receive audio input from the computer's sound card and produce audio output in the form of sound waves.
Spyware: 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.
SRS Tru-Surround XT: Tru-Surround XT is a sound-scheme that has the ability to take multi-channel encoded sources, such as Dolby Digital, and reproduce the multi-channel surround effect by just using two-speakers. The result is not as impressive as true Dolby Digital 5.1 (the front and side surround effects are impressive, but the rear surround effects fall a little short, with the sense they are coming from just to rear of your head rather than from the back of the room).
SSD: SSD is short for "Solid State Drive." An SSD serves the same purpose as a (hard drive/hard drive), but uses flash memory rather than spindle of magnetic disks. It is called a "solid state drive" because it has no moving parts. Since SSDs do not need to move a physical drive head to read data, they can access data faster than hard drives.
SSID: 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.
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.
STB: Set-Top Box. A device for decoding incoming AV signals, such as programs from a cable or satellite TV network. Almost all STBs currently rely on HDMI output.
Storage Capacity: Storage capacity is another term for "disk space." It measures how much data a computer system may contain. For example, a computer with two 750GB hard drives has a storage capacity of 1.5TB. Storage capacity is commonly included in the technical specifications of a system, along with processing power and memory. It is possible to increase the storage capacity of most systems by adding additional internal or external hard drives.
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. 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. Netflix, Hulu, and Youtube are examples of sites that stream video and audio. 
Stretching: Redefining the black or white points in an image to increase the contrast.
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.
Subwoofer: A subwoofer is a speaker that is specifically designed only to reproduce the lowest of audible frequencies. It is dedicated to the reproduction of low-pitched audio frequencies known as bass.
Surge Protector: The surge protector is an important part of any setup. It allows multiple devices to plug 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.
Surround Sound: Surround sound is a term applied to several types of processes that enable the listener to experience sound coming from all directions, depending on the source material.
SVGA: Acronym for Super Video Graphics Display. SVGA is used to define a specific display resolution equating to 800x600 pixels.
S-Video S-Video refers to analog video connection in which the B/W and Color portions of the signal are transferred separately. The signal is then recombined by the Television or video recording device at the receiving end. The result is less color bleeding and more defined edges than with a standard analog composite video connection.
S-Video: S-Video refers to analog video connection in which the B/W and Color portions of the signal are transferred separately. The signal is then recombined by the Television or video recording device at the receiving end. The result is less color bleeding and more defined edges than with a standard analog composite video connection.
SXGA: Acronym for Super Extended Graphics Adapter. SXGA is used to define a specific display resolution equating to 1280x1024 pixels.
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 your 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.
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.