Bitmap
A kind of graphic made up of pixels. A bitmap is created whenever an image is scanned. It can then be saved as a  JPEG, GIF, or other type of file.

Bit-mapped Graphics
Bit-mapped graphics is the TV-like method that uses dots to display an image on screen. Bit-mapped images are created by scanners and cameras and are also generated by paint packages. A picture frame is divided into hundreds of horizontal rows, with each row containing hundreds of dots, called pixels. Programs that manipulate bit-mapped images are called paint programs.

Byte
The amount of memory space used to store one character, which is usually 8 bits.

Bookmark
A feature of most Web browsers. A stored location for quick retrieval at a later date. Web browsers provide bookmarks that mark a location users want to revisit in the future. It contains the address (URL) of a favorite site so it can be found immediately without having to look up the URL and type it in.

Browser
A client program that allows users to read hypertext documents on the World Wide Web, and navigate between them. Examples are Netscape Navigator, Lynx, and Microsoft Internet Explorer. Browsers can be text-based or graphic.

Buffer
A reserved area of memory for temporarily holding data. A buffer can hold data being sent from a high-speed device to a low-speed device until the slower device can accept the input; for example, to hold data sent to a printer until the printer is ready for it.

Bus
A collection of wires through which data is transmitted from one part of a computer to another. It is called a bus because it travels to all destinations.

Cache
Pronounced "cash." A temporary storage area for frequently-accessed or recently-accessed data. Having certain data stored in cache speeds up the operation of the computer. There are two kinds of cache: internal (or memory cache) and external (or disk cache). Internal cache is built into the CPU, and external cache is on the motherboard. When an item is called for, the computer first checks the internal cache, then the external cache, and finally the slower, main storage.

Cascading Windows
Displaying windows in a progressive order so that all the title bars appear on screen at one time.

Cartridge
A self-contained, removable module that is inserted into a slot in the computer or printer. Toner or ink cartridges are used in the printer; magnetic tape is protected within a cartridge; and game software in the form of plug-in cartridges is popular. Memory chips can come in cartridges; a font cartridge is one example.

CD
Compact Disc. A format for storing audio data in digital form, which can be played on a CD player or with a CD-ROM drive. A CD is a digital audio disc that contains up to 74 minutes of hi-fi stereo sound. Introduced in 1982, the disc is a plastic platter 120mm (4.75") in diameter, recorded on one side, with individual selections playable in any sequence.

CD-ROM
Compact Disc Read-Only Memory. An optical disc that is physically the same as an audio CD, but contains computer data. Storage capacity is about 680 megabytes. CD-ROMs are interchangeable between different types of computers.

Channel
This is when two devices are linked either externally or internally, as in a path between two computers. It can be either the wires or the frequencies at which radio waves are transmitted.

Character
A symbol that represents information, or the representation of that symbol by a computer. Letters of the alphabet, numbers, and punctuation symbols are characters. A character is equivalent to a byte.

Chip
Also called microelectronic or integrated circuit. A microelectronic device comprising many miniature transistors and other electronic components on a single thin rectangle of silicon or sapphire, approximately 1/16" to 5/8" on a side, and 1/30" thick.

Client
A client application is one that resides on a user's computer, but sends requests to a remote system to execute a designated procedure using arguments supplied by the user. The computer that initiates the request is the client and the computer responding to the request is the server. Many network services follow a client and server protocol.

CMYK
(Cyan Magenta Yellow blacK) The color model used for commercial printing and most color computer printers. In theory, cyan, magenta and yellow (CMY) can print all colors, but inks are not pure and black comes out muddy. The black ink (K) is required for quality printing.

Code
1.A set of symbols that represent assigned, possibly secret meanings. 2.To put a communication into coded form. 3.Computer programming instructions. 4.To write computer instructions.

Component
One element of a larger system. A hardware component can be a device as small as a transistor or as large as a disk drive as long as it is part of a larger system. Software components are routines or modules within a larger system.

Connector
Any plug and socket that links two devices together. When not designed or constructed properly, they often become the weakest element in an electronic system.

Controller
An electronic circuit board or system. In a personal computer, controllers contain the circuitry to run a peripheral device and are either contained on a plug-in expansion board or on the motherboard. Increasingly, plug-in boards for disk control, networking, sound, etc., are being replaced by built-in circuits (chips) on the motherboard.

Cookie
A cookie is a set of data that a website server gives to a browser the first time the user visits the site, that is updated with each return visit.The remote server saves the information the cookie contains about the user and the user's browser does the same, as a text file stored in the Netscape or Explorer system folder.

CPU
Central Processing Unit. The CPU controls the operation of a computer. Units within the CPU perform arithmetic and logical operations and decode and execute instructions. In microcomputers, the entire CPU is on a single chip.

Cross-Platform
Refers to software (or anything else) that will work on more than one platform (type of computer). For instance, the Windows platform or the Macintosh platform.

Data
Information; raw facts. Data can be input into a computer and processed in various ways. For a computer to process data, it must be translated into a form the computer can handle. The human brain also processes data fed to it by the sensory organs.

Database
A large collection of data organized for rapid search and retrieval or a program that manages data, and can be used to store, retrieve, and sort information.

Default
An instruction that a computer assumes, unless the user gives it other instructions. For example, if the default typeface on a word processing program is Times Roman, the user may instruct the machine to use a different default typeface; once the program is opened, a variety of types may be used, regardless of the default setting.

Density
How tightly information is packed together on a disk. A higher density means that information is closer together, so the disk can hold more.

Desktop
The whole computer screen, which represents an office desktop.With a graphical interface, the icons on the screen resemble objects that would be found on a real desktop, such as file folders, a clock, etc.

Device
Any machine or component that attaches to a computer. Examples of devices include disk drives, printers, mice, and modems. Device always refers to hardware.

Digital
Describes any system based on discontinuous data or events. Computers are digital machines because at their most basic level they can distinguish between just two values, 0 and 1, or off and on. There is no simple way to represent all the values in between, such as 0.25. All data that a computer processes must be encoded digitally, as a series of zeroes and ones.

Disk
A round plate on which data can be encoded. A direct access storage device. Types of disks include the floppy disk, hard disk, magnetic disk, optical disk, CD-ROM and DVD.

Domain Name
An Internet address in alphabetic form. Domain names must have at least 2 parts: the part on the left which names the organization (shermanisd), and the part on the right which identifies the highest subdomain, such as the type of organization (.net for network; .com for commercial; .edu for educational, etc.).

Dot-Matrix Printer
A kind of impact printer that uses small closely packed needles or "pins" and an ink ribbon to make a pattern of tiny dots which form the letters on a page. Dot matrix printers are noisy and cannot print fine-quality type, but are also inexpensive and have many uses.

Double-Density
(DD) Double-density disks have twice as much storage space per unit area than the outdated single-density format. Double-density 3.5" floppy disks are 720k.

DPI
Dots Per Inch: A measure of the resolution of printers, scanners and monitors. The more dots per inch, the higher the resolution: 600 dpi would mean 600 x 600 = 360,000 dots per square inch. 300 DPI is considered to be photo quality. If an image is being used on the web or for computer screen purposes, then it needs to be 72 DPI, since that's all most computer screens can display.

Driver
A driver is a program that extends the operating system to support a device such as a disk or tape drive; or a program that enables an application to use a device such as a printer. Hardware devices such as sound cards, printers, scanners, and CD-ROM drives must each have the proper driver installed in order to run.

DVD
Digital Versatile Disc or Digital Video Disc. An optical storage medium which has greater capacity and bandwidth than a CD. DVDs can be used for multimedia and data storage. A DVD has the capacity to store a full-length film with up to 133 minutes of high quality video in MPEG-2 format, plus audio.

DVD-ROM
Digital Video Disc-Read Only Memory. A disc like a CD-ROM that has more storage (4.7 gigabytes) and can provide digital video. DVD-ROMs with 17GB storage will soon be available.

DVD-Video
A read-only DVD disc used for full-length movies. DVD-Video discs hold approximately 133 minutes of full-motion video per side using MPEG-2 compression. The first DVD-Video players became available at the end of 1996.

Embedded Object
An object, such as a graphic, which has been placed in a document from another file.

Ethernet
The most popular type of local area network, which sends its communications through radio frequency signals carried by a coaxial cable. Each computer checks to see if another computer is transmitting and waits its turn to transmit.

Expansion Board
A printed circuit board, also called an expansion card, which can be plugged into the computer's expansion slot to add a new feature.

Field
One of the items in a database record: for example, Name, City, Zip Code, etc. A field may have a specific number of characters or may vary. A group of fields make up a record.

Firewall
An electronic boundary that prevents unauthorized users from accessing certain files on a network; or, a computer used to maintain such a boundary.

Font
A complete set of type characters of a particular typeface design and size. Usually, each typeface (Times New Roman, Arial, etc.) is made available in four variations: normal weight, bold, italic and bold italic.

Format (disk)
Preparing a disk so a computer can read and write data on it. Formatting a disk includes creating the physical tracks and sector identification, and creating the indexes specific to the operating system it will be used on. Floppy disks can be bought preformatted or can be formatted by the user with a program on the computer.

Floppy Disk
A removable, portable magnetic disk on which data and programs can be stored. Also called diskettes, floppies are flexible plastic. The older 5-1/4 inch disks are more flexible; the 3-1/2 inch disks have a hard protective case around them and are the primary size used now.

FTP
File Transfer Protocol. A client/server protocol for exchanging files with a host computer over a TCP/IP network. For example, after developing the HTML pages for a Web site on a local machine, they are typically uploaded to the Web server using FTP.

GIF
Graphics Interchange Format. A format used for displaying bitmap images on World Wide Web pages, usually called a "gif" because .gif is the filename extension. These files use lossless compression and can have 256 colors. JPEG and GIF are commonly used for images on the Web; JPEG is considered best for photos and GIF for other graphic images.

Gigabyte
(GB) One billion bytes or approximately 1,000 megabytes.

Graphical User Interface (GUI)
A graphics-based user interface that incorporates icons, pull-down menus and a mouse. The GUI has become the standard way users interact with a computer.

Graphics
The creation and manipulation of picture images in the computer, typically called computer graphics. Computer graphics has two main methods for storing and maintaining pictures in a computer: vector graphics and bitmapped graphics.

Handshaking
The exchange of signals back and forth over a communications network to establish a valid connection between two computers.

Hard Disk
The main device that a computer uses to store information. Hard disks are rigid aluminum or glass disks about 3.5" in diameter in a personal computer, and smaller in a laptop. They are coated with ferromagnetic material and rotate around a central axle. Data is transferred magnetically by a read/write head. A hard disk drive for a personal computer may contain as many as eight hard disks, rotating around the same axle.

Hardware
The hardware is the physical part of a computer system; the machinery and equipment (CPU, disks, printers, monitor, keyboard, modem, cables, etc.)

Hierarchical File System
A file organization method that stores data in a top-to-bottom organization structure. All internal access to the data starts at the top and proceeds throughout the levels of the hierarchy.

High-Density
(HD) Having high storage capacity per unit of area. High-density disks store more information than double-density disks.Currently, high-density 3.5" floppies are 1.4 MB.

Host
A computer connected to a network, that provides data and services to other computers. Services may include data storage, file transfer, data processing, e-mail, bulletin board services, World Wide Web, etc.

HTML
HyperText Markup Language. The document format used on the World Wide Web. Web pages are built with HTML tags (codes) embedded in the text. HTML defines the page layout, fonts and graphic elements as well as the hypertext links to other documents on the Web. Each link contains the URL, or address, of a Web page residing on the same server or any server worldwide, hence "World Wide" Web.

Hypertext
Text that has hyperlinks.When hypertext is viewed with an interactive browser, certain words appear as highlighted by underlining or color; clicking on a highlighted link leads to another location with more information about the subject. The term was invented by Ted Nelson.

Icon
In a graphical user interface, a small picture on the screen which represents something. Files and programs have icons, and open when the user clicks twice on the icon. There is an icon to show which program is currently running. Moving and copying files is done by dragging their icons to the desired location. A file is deleted by moving its icon to the picture of a trash can.

Ink-Jet Printer
A printer that propels droplets of ink directly onto paper. Today, almost all ink jet printers produce color, or at least have a color option. Low-end ink jets use three ink colors (cyan, magenta and yellow), but produce a composite black that is often muddy. Four-color ink jets (CMYK) use black ink for pure black printing. Ink jet printers are affordable, quiet and very popular.

Input
To enter data into a computer; or, the data that is input.

Integrated Circuit
The formal name for the chip. In 1958, TI inventor Jack Kilby demonstrated the first electronic circuit in which more than one transistor was fabricated on a single piece of semiconductor material. It was about half the size of a paper clip.

Interface
A shared boundary where two or more systems meet. Click the link to read about three types of interfaces.

Internet
With a small i, an internet is short for internetwork. It is a network of networks; a group of networks interconnected via routers. With a capital I, The Internet is the biggest internet in the world. This worldwide information highway is comprised of thousands of interconnected computer networks, and reaches millions of people in many different countries.

Intranet
A local area network which may not be connected to the Internet, but which has some similar functions. Some organizations set up World Wide Web servers on their own internal networks so employees have access to the organization's Web documents.

IP
IP by itself is something like the postal system. It allows you to address a package and drop it in the system, but there's no direct link between you and the recipient. TCP/IP, on the other hand, establishes a connection between two hosts so that they can send messages back and forth for a period of time.

ISP
Internet Service Provider. An organization that provides access to the Internet. Customers are generally billed a fixed rate per month, but other charges may apply. For a fee, a Web site can be created and maintained on the ISP's server, allowing the smaller organization to have a presence on the Web with its own domain name.

JavaScript
A popular scripting language that is widely supported in Web browsers and other Web tools. It adds interactive functions to HTML pages, which are otherwise static, since HTML is a display language, not a programming language.

JPEG
Joint Photographic Experts Group. A format for storing high-quality color and grayscale photographs in bitmap form; also the group that developed the format. JPEG provides lossy compression by segmenting the picture into small blocks which are divided to get the desired ratio; the process is reversed to decompress the image. JPEG uses the JPEG File Interchange Format, or JFIF.

Kernel
The essential part of a program or operating system, that performs the basic functions. Typically, the kernel is responsible for memory management, process and task management, and disk management.

Kilobyte
(k, KB) Approximately one thousand bytes. A unit of measurement used for computer file sizes.

Laser Printer
A high-speed, non-impact printer that uses a laser beam to form images on a page. Laser printers work like photocopiers to produce high-resolution, high-quality printouts.

Linked Object
Paste a copy of an object into a document in such a way that it retains its connection with the original object. The link refers to data or the location of data in another record.

Listserv
LISTSERV is currently a commercial product marketed by L-Soft International. Although LISTSERV refers to a specific mailing list server, the term is sometimes used incorrectly to refer to any mailing list server.

Local-Area Network (LAN)
A network of directly-connected machines (usually in the same building), providing high speed communication over physical media such as fiber optics, coaxial cable, or twisted pair wiring.

Lossy Compression
A compression technique in which a file can be highly compacted, but some data is lost.Large files such as graphics, video, or audio files can be stored in a smaller amount of space than with lossless compression, but some loss of quality will result when the file is decompressed.

Magnetic Disk
The primary computer storage device. Like tape, it is magnetically recorded and can be re-recorded over and over. Disks are rotating platters with a mechanical arm that moves a read/write head between the outer and inner edges of the platter's surface. It can take as long as one second to find a location on a floppy disk to as little as a couple of milliseconds on a fast hard disk.Examples are floppy disk and hard disk.

Mailing List
An email discussion forum. Participants subscribe to a list, receive copies of messages sent by other members, and can email their own comments. In some mailing lists there is a moderator who receives all mail, screens it, and decides which messages to pass on. Unmoderated lists simply redirect all mail received to the list of recipients.

Megabyte
(MB) Used to describe data storage. Approximately 1 million bytes or 1,000 kilobytes.

Memory
The computer's temporary workspace (physically, a collection of RAM chips). It is an important resource, since it determines the size and number of programs that can be run at the same time, as well as the amount of data that can be processed instantly.

Metasearch Engine
Software that is used on a Web site to search other Web search sites. For instance, Dogpile is a search site that will search the individual sites Google, Overture, Ask Jeeves, Looksmart, Inktomi, About, FindWhat, and FAST all in one search.

Microcomputer (Personal Computer)
Generally synonymous with personal computer, such as a Windows PC or Macintosh, but it can refer to any kind of small computer. When the term was first introduced, it meant a computer with a single microprocessor chip as its CPU, namely, the personal computer. Today, most every computer uses at least one microprocessor CPU, including desktop PCs, high-end workstations, small, medium and large servers and even mainframes.

Microprocessor
A computer with its entire CPU contained on one integrated circuit. The first microprocessor was created by Intel. The creation of microprocessors was the breakthrough that led to the development of personal computers. Microprocessors have, over time, acquired more and more of the features of large computers.

Motherboard
The main circuit board inside a computer, which contains the central processing unit, the bus, memory sockets, expansion slots, and other components.

MPEG
Moving Pictures Experts Group.1. An ISO (International Standards Organization) group that sets standards for compressing and storing video, audio, and animation in digital form. 2. The standards set by this group. MPEG is a lossy compression method. MPEG-1 is a standard for CD-ROM video and audio.MPEG-2 is a standard for full-screen, broadcast quality video. MPEG-4 is a standard for video telephony.

Multimedia
Multimedia is communication that uses any combination of different media, and may or may not involve computers. Multimedia may include text, spoken audio, music, images, animation and video. The large amounts of data required for computer multimedia files makes CD-ROMs a good option for storage; but there are other ways of receiving multimedia communications, such as the World Wide Web. Multimedia programs are often interactive, and include games, sales presentations, encyclopedias, and more.

Multiprocessing
Using two or more processors in the same computer, or two or more computers connected together, to execute more than one program or instruction at the same time.

Multitasking
Running more than one program at a time. When a machine has this capability, it is easy to switch between programs without having to quit, or to copy material from a file in one program to a file in another.

Network
A group of interconnected computers, including the hardware and software used to connect them.

Node
In communications, a node is a network junction or connection point. For example, a personal computer in a network is sometimes called a node.

Object
In a compound document, an independent block of data, text or graphics that was created by a separate application.

OLE
Object Linking and Embedding. A way of connecting a file with objects from other applications. For example, a page layout file could have a spreadsheet chart, a word processing file, and a graphics file included. An embedded object becomes part of the document in which it is embedded, and is no longer linked to the source document.

Operating System
The master control program that runs the computer. The first program loaded when the computer is turned on, its main part, the "kernel," resides in memory at all times. The operating system sets the standards for all application programs that run in the computer. The applications "talk to" the operating system for all user interface and file management operations.

Optical Character Recognition
(OCR). The ability of a computer to recognize characters optically. OCR programs are used with scanners to enter text into the computer when there is already a hardcopy version. A page of text scanned with OCR does not read as a graphics file, the way other scanned images do. It can be edited and formatted just like any other text file. Text scanned with OCR will lose some of its formatting, and when a letter is indistinct, the program will guess, so typos can creep in.

Optical Disk
A direct access disk written and read by light. CD, CD-ROM, DVD-ROM and DVD-Video are read-only optical disks that are recorded at the time of manufacture and cannot be erased. CD-R, DVD-R, WORM and magneto-optic (in WORM mode) disks are write-once. They are recorded in the user's environment, but cannot be erased. CR-RW, DVD-RAM, DVD-RW and MO disks are rewritable.

Output
Information that comes out of the computer; for example, a picture on the screen, a printed page, sound coming from the speakers, files printed to disk or sent over a communications line.

Packet
A unit of data formatted for transmission on a network. Data is broken up into packets for sending over a packet switching network. All the data packets related to a message may not take the same route to get to their destination; they are reassembled once they have arrived.

Parallel
Side by side. For example, a parallel interface can transmit eight bits (a whole byte) at one time, over eight parallel lines. A serial interface transmits only one bit at a time.

PCMCIA
(Personal Computer Memory Card International Association). A Sunnyvale, California nonprofit trade association created to standardize the connection of peripherals to portable computers. PCMCIA developed the PC Card (often called the PCMCIA card), a lightweight, removable module about the size of a credit card that adds features to a portable computer.

Peripheral Device
A piece of hardware that's outside the main computer. Any hardware device connected to a computer, such as a monitor, keyboard, printer, disk, tape, graphics tablet, scanner, joy stick, paddle and mouse.

Plug-in
An accessory program that enhances a main application. An example is the set of additional tools and effects available to Photoshop image editor in the Plug-ins folder. There are many plug-ins for Netscape Navigator such as Shockwave and QuickTime that give the browser special capabilities, especially for multimedia Web sites.

Pointing Device
An input device used to move the pointer (cursor) on screen. The major pointing devices are the mouse, trackball, pointing stick and touchpad.

Port
Can mean a socket at the back of a computer used to plug in external devices such as a mouse, scanner, or printer.

Primary Storage
The computer's internal memory (RAM).

Printed Circuit Board
The flat board in a computer that holds integrated circuits and other electronic components. Often called a card or adapter.

Programmer
A person who writes instructions (programs) for computers.

Protocol
Often simply referred to as a protocol, a communications protocol is a set of rules or standard designed so that computers can exchange information with a minimum of errors.

Query
To request information from a database.
In a database, a group of fields that make up one complete entry. A record about a person might contain fields for name, address, telephone, etc. A group of records makes up a file or database.

RAM
Random Access Memory. The working memory of the computer. RAM is the memory used for storing data temporarily while working on it, running application programs, etc. RAM chips require power to maintain their content, which is why you must save your data onto disk before you turn the computer off.

Record
In a database, a group of fields that make up one complete entry. A record about a person might contain fields for name, address, telephone, etc. A group of records makes up a file or database.

Resolution
The number of dots per square inch required to produce a high-quality image in printing or on a computer display screen. The higher the resolution, the finer the image quality. Good laser or inkjet printers and scanners provide a resolution of 600 dots per inch.

Resource
A facility of a computing system needed in order to perform an operation or task. Resources include memory, storage, input/output units, processing units, data sets, files, and programs.

RGB
(Red Green Blue) The color model used for generating video on a display screen. It displays colors as varying intensities of red, green and blue dots. The three primary colors of light which, mixed together in various proportions, produce all the other colors. In a color cathode ray tube three electron guns direct these three colors of light at the screen in separate beams.

Router
A device that finds the best path for a data to be sent from one network to another. A router stores and forwards electronic messages between networks, first determining all possible paths to the destination address and then picking the most expedient route, based on the traffic load.

Search Engine
A program on the Internet that allows users to search for files and information. Although a search engine is the software used to perform a search, the term has become synonymous with the Web site itself. For example, Google is a major search site on the Web, but rather than being called the "Google search site," it is commonly known as the "Google search engine."

Secondary Storage
External storage, such as disk and tape. Also referred to as mass storage.

Sector
Sectors are pie-sliced divisions of a disk. They are the smallest unit of storage read or written on a disk.

Semiconductor
A solid state substance that can be electrically altered. Certain elements in nature, such as silicon, perform like semiconductors when chemically combined with other elements. A semiconductor is halfway between a conductor and an insulator. The most significant semiconductor is the transistor, which is simply an on/off switch.

Serial
One at a time. In serial transmissions, one bit at a time is sent over the serial line.

Serif and Sans Serif
The two categories of typefaces. Serifs have a short finishing stroke at the end of and at an angle to each stroke in a letter. An example is Times New Roman. Serifs are thought to make type more readable, and are often used in book and newspaper text. Fonts without serifs are called san serif fonts. An example is Arial.

Server
A computer or device on a network that manages network resources. For example, a file server is a computer and storage device dedicated to storing files. Any user on the network can store files on the server. A print server is a computer that manages one or more printers, and a network server is a computer that manages network traffic.

Sheet Feeder
A mechanical device attached to a printer which automatically feeds sheets of paper or forms from an input drawer into the printer, and which feeds the finished printed pages into an output drawer. Most printing instructions allow a choice between using the sheet feeder or the manual feed.

Silicon
(Si) An element found in rocks and sand, which is used as the base, or substrate, for computer chips.

Software
Instructions for the computer. A series of instructions that performs a particular task is called a "program." The two major categories of software are "system software" and "application software."

Speech Synthesis
The generation of speech by a machine, from text input. Speech synthesis is used to enable blind users to read text. Synthesized speech is not hard to recognize, because it lacks normal spoken inflection.

Spreadsheet
A table which displays numbers in rows and columns, used for accounting, budgeting, financial analysis, scientific applications, and other work with figures. Originally, paper spreadsheets were used; the computerized versions have the advantage of being able to perform automatic calculations on changing data.

Storage
The semi-permanent or permanent holding place for digital data. Storage means disks and tapes, not memory.

Storage Device
A peripheral unit that holds data. Tapes and disks are storage devices.

Surge Protector
An electrical device that protects a computer from spikes and surges in the power line. All computers have some surge protection built in, but this protection is not always enough. External surge protectors come in the form of a unit that plugs into the wall, with outlets for several electrical plugs. However, not all outlet bars have surge protection.

System Software
Programs used to control the computer and develop and run application programs. It includes operating systems, network operating systems and database managers and drivers.

Tape
A data storage medium used for backup. The tape is made of a thin plastic strip with a magnetisable oxide coating on one side. To read or write, the tape drive winds the tape from one reel to another, causing it to move past a read/write head. Tapes are available in reels and cartridges of various sizes. The data is written in blocks with interblock gaps between them. To find a specific block of data on the tape the computer must read everything in front of it.

Task
In a multitasking environment, an independently running program or subprogram.

TCP
TCP enables two hosts to establish a connection and exchange streams of data. TCP guarantees delivery of data and also guarantees that packets will be delivered in the same order in which they were sent.

TCP/IP
(Transmission Control Protocol/Internet Protocol) The Transmission Control Protocol (TCP) on top of the Internet Protocol (IP). These protocols were developed by DARPA to enable communication between different types of computers and computer networks.

Telephony
Transmission of voice or other sound by means of electrical signals sent over wires or radio waves.The sound waves are converted into electrical signals for transmission, and converted back into audio signals at the receiver.

Teleconferencing
Interactive communication among several people at different locations ("tele-" means long distance). It may involve audioconferencing (sound only), videoconferencing, or data conferencing.

Toner
An electrically charged ink in the form of a powder which is used in an electrostatic process by laser printers and copy machines to create images on the paper.

Toolbar
A vertical or horizontal bar containing icons that represent the commands that can be used in an application. Sometimes the toolbar can be moved around or made to disappear. Your taskbar, which is a little different from a toolbar, is the long gray bar that sits at the bottom of your screen. It has the Start button, system tray, and possibly more on it. In addition, it's where your program buttons sit.

Track
Tracks are recorded onto a floppy disk during formatting; a high-density floppy has 160 tracks.Disk storage is organized in tracks and sectors, which are pie-shaped slices.

Transitor
A device used to amplify a signal or open and close a circuit. In a computer, it functions as an electronic switch or bridge. The transistor contains a semiconductor material that can change its electrical state when pulsed.

Typeface
The design of a set of printed characters, such as Courier, Helvetica and Times Roman. The terms "typeface" and "font" are used interchangeably, but the typeface is the primary design, while the font is the particular implementation and variation of the typeface, such as regular, bold, italic or bold italic.

Upgrade
To replace existing software with a newer version. The terms upgrade and update are used synonymously although update generally refers to adding and deleting elements of data in a file or database and upgrade refers to changing to new software.

URL
Uniform Resource Locator. An Internet address which tells a browser where to find an Internet resource. For example, the URL for SISD is http://www.shermanisd.net/. It is the address that defines the route to a file on the Web or any other Internet facility. URLs are typed into the browser to access Web pages, and URLs are embedded within the pages themselves to provide the hypertext links to other pages.

USB
Universal Serial Bus. A personal computer external bus standard. A single USB port can be used to connect up to 127 peripheral devices, such as mice, modems, and keyboards in a daisy chain configuration, can support plug-and-play (hot plugging), and has a total bandwidth of 1.5 megabytes per second. It uses inexpensive cable, which can be up to 5 meters long.

User
An individual who uses a computer, program, network, or related service for work or entertainment; usually there is a distinction between a user and a programmer or other person who works with the computer on an expert or technical level.

User Interface
The combination of menus, screen design, keyboard commands, command language and online help, which creates the way a user interacts with a computer. If input devices other than a keyboard and mouse are required, this is also included. In the future, natural language recognition and voice recognition will become standard components of the user interface.

Vector Graphics
Maintains the image as a series of points, lines, arcs and other geometric shapes. In vector graphics, the image is saved as a file containing instructions for drawing it. One advantage of vector graphics over raster graphics is that a picture can be enlarged or reduced without losing quality. Programs that enable you to create and manipulate vector graphics are called draw programs.

Videoconferencing
Teleconferencing in which still or moving pictures can be transmitted along with voice and text. The first videoconferencing was done with analog TV and satellites, then digital video systems, using computer networks, evolved.

Virtual
An adjective that expresses a condition without boundaries or constraints. It is often used to define a feature or state that is simulated in some fashion. For example, one of the first uses of the term was for "virtual memory," in which memory is saved to disk and swapped back and forth as needed, thus memory is essentially "simulated on disk."

Virus
A program or piece of code that infects a computer by atttaching itself to another program, and propagating itself when that program is executed. A computer can become infected by files downloaded over a network, or by the installation of new software or floppy disks that are infected with viruses.

Web Host
A web hosting company (usually an ISP) leases server space and web services to companies and individuals who wish to present a web or e-commerce presence but do not wish to maintain their own servers.

Web Page
A World Wide Web document. A web page is usually a file written in HTML and stored on a server. A web page usually has links to other web pages. Each web page has its own address called a Uniform Resource Locator (URL). It may also contain JavaScript code or other commands.

Web Server
A server on the Internet that holds World Wide Web documents and makes them available for viewing by remote browsers.

Web Site
A server on the Internet that holds World Wide Web documents and makes them available 24 hours a day for viewing by remote browsers.

Whiteboard
The equivalent of a blackboard, but on a computer screen. A whiteboard allows one or more users to draw on the screen while others on the network watch, and can be used for instruction the same way a blackboard is used in a classroom. Also used for videoconferencing.

Wide-Area Network (WAN)
A network spanning multiple geographic distances, usually connected by telephone lines, microwave, or satellite links. Typically consists of two or more local-area networks (LANS).

Window
Each part of a window in the Windows operating system has a name. The list at the top of each window (usually starts with File, Edit, etc) is called the Control Menu. The name at the top of the window is called the Title Bar. The three buttons at the top right are the Minimize, Maximize, and Close buttons. All the way to the right, you may have a Vertical Scroll Bar, and at the bottom, a Horizontal Scroll Bar. Each scroll bar has a Scroll Box, and at each end of the scroll bar are Scroll Arrow Buttons. The window itself is generally referred to as the Workspace and the edge of the window is the Border.

Wizard
1. A program utility that works as an interactive guide by walking the user step-by-step through an unfamiliar task. For example, a Word wizard might assist the user in drafting a business letter. 2. An expert hacker or computer programmer. 3. A privileged user on a system, who has powers beyond those of the ordinary user.

Word Processing
The preparation of text documents, usually by means of a computer. Word processing is a stage of desktop publishing: the preparation of text, rather than the design. Some features provided by word processing software include word wrap, text editing functions, type styling, page formatting, search and replace, spelling and grammar checking, style sheets, headers and footers, page numbering, sorting, and mail merge.

Workstation
1. A one-person computer that is more powerful and faster than most personal computers, and is typically used for graphics, scientific computing, CAD (Computer-Aided Design), CAE (Computer-Aided Engineering), and other applications requiring high performance and memory.
2. A terminal in a network, which may have its own processing capability.
3. A terminal or personal computer where one person works.

World Wide Web
(WWW) A hypermedia-based system for browsing Internet sites .It is named the Web because it is made of many sites linked together; users can travel from one site to another by clicking on hyperlinks. Text, graphics, sound, and video can all be accessed with browsers like Mosaic, Netscape, or Internet Explorer.

Worm
A destructive program that replicates itself throughout disk and memory, using up the computers resources and eventually putting the system down.

Zip Drive
A small, lightweight, portable disk drive from Iomega, which uses 100 or 250 megabyte 3.5" removable cartridges. They are used for backing up hard disks and for transporting large files.