10Base2: Ethernet running on thin coaxial cable.

10Base5: Ethernet running on thick coaxial cable.

10Base-T: Ethernet running on twisted pair cable. It looks like phone cord but the modular plugs at the end, RJ-45 connectors, are slightly larger.

3D graphics: Computer graphics based on computer generated objects with height, depth, and width information.

8088: Processor found in IBM XT and compatible computers.

80286: Processor found in the IBM AT and compatible computers.

80386: Processor that features a 32-bit data path. It is also available in a lower cost version, the 80386sx, which has a 16-bit data path, and, therefore, is somewhat slower.

80486: The 80486 processor has a built-in math coprocessor and is significantly faster than the 80386. There are variations in the 80486, including the 80486SX, which does not have a functioning math coprocessor, the 80486DX2, which runs internally at double the clock speed at which it communicates with the rest of the computer, and the DX4, which runs at a quadruple internal speed.

80586: (See Pentium.)

Active Application: An application that is currently running and is in the foreground. The active application is the one you are currently able to work in.

AC Adaptor: Device which transforms alternating current (AC) electricity into a form that a devices like laptops and notebooks can use.

Access: Entry to or communication with a particular object, such as an operating system, specific files, or accounts.

Active Matrix Screen: A type of liquid crystal display (LCD) screen used on portable computers. Each pixel has a separate circuit, which enables each pixel to be activated completely independently. An active matrix screen also allows the pixels to be addressed more quickly than a passive matrix display.

Address Mask: A bit mask used to select bits from an Intranet provider (IP) address for subnet addressing. The mask is 32 bits long and selects the network portion of the IP address and one or more bits of the local portion.

Anonymous FTP: (See FTP.)

ANSI: American National Standards Institute. A standards organization that sets standards for the U.S. computer industry. For instance, ANSI participates in defining network protocol standards.

Application: A program. Programs such as Microsoft Word, Excel, Photoshop, etc. are applications. Applications give your computer instructions that provide you with tools to accomplish a task. For instance, a word processing application provides space to type in, means to format the text, a spelling checker, etc.

Architecture: The structure and organization of a computer's hardware or system software, including items such as the central processing unit (CPU) type, bus type, etc.

ARP: Address Resolution Protocol. The Transmission Control Protocol/Internet Protocol (TCP/IP) used to dynamically bind a high level IP address to a low-level physical hardware address.

Arrow Keys: Also called direction or cursor keys. Keys used at times to navigate around the screen, often used in text areas. Arrow keys have arrows pointing up, down, right, and left.

ASCII: American Standard Code for Information Interchange. The American Standard Code for Information Interchange 7-bit character set. It consists of the first 128 (0-127) characters of the ANSI character set (and most other 8-bit character sets). The ASCII character set is the most universal character-coding set.

ASCII text file: A file that contains nothing but ASCII characters without special formatting. ASCII text files are sometimes used in file transfers.

AT: Any International Business Machine Corporation (IBM) or compatible computer that contains an 80286 processor and 16-bit bus.

Autoconfig: Automatic configuration. The ability of computer hardware to detect the presence of expansion devices, and, using information resident in those devices, configure the system to run the device properly. Also known as plug and play.

AUTOEXEC.BAT: A batch program (set of commands) that is automatically carried out by MS-DOS whenever the computer is started or restarted. The file contains basic startup commands that help configure the system. Often, when a computer stops doing what it normally does when it boots, it is because the autoexec.bat file has been deleted. It is a good idea to have a copy of the autoexec.bat file (printed or on a separate disk) in case this happens.

Backbone: A network that connects other networks.

Background: The area behind and outside the active window, including the desktop and any other application windows or icons. Applications can also run in the "background." These applications are still running but they are not in the active window and they continue to run without user intervention.

Backup: Backup is the process of preserving copies of files on a different drive, directory, or media (often floppy disks or tape) to protect against the destruction or loss of the original files in the event of hardware or system failure. Two backups are often recommended: one onsite and another offsite.

BASIC: Beginners All Purpose Symbolic Instruction Code. An easy to learn and once popular programming language. BASIC is not as commonly used today.

Batch File (Batch Program): An ASCII text file that contains a list of DOS commands and program names. When the batch file is run, the commands and programs are run in sequence just as if you had typed them at the MS-DOS prompt. Batch files are distinguished by their ".BAT" suffix.

Baud Rate: Speed at which information is transferred. Generally referred to as bits per second (bps) now.

BBS: (See Bulletin Board System.)

Benchmark: Test of performance of a computer or peripheral device. While benchmarks can offer seemingly objective tests of performance, the best test is to use the computer or peripheral with the applications and files you will actually be using.

Beta: A designation of pre-release software. A beta version of software is usually in secondary testing (alpha versions are earlier releases), and is sometimes publicly available, but sometimes only available to particular users (beta testers). Beta software is often somewhat unstable, and may have more bugs than a regular release.

Binary file: A file that contains information in machine-readable form; it can be read only by an application. "Binary_file" usually refers to a file that uses all eight bits of each byte for information. Text files usually use only seven bits, leaving the eighth bit as 0.

Binary transfer: Method of transferring files to or from a remote computer in which all eight bits of each byte are transferred. In a text transfer, the eighth bit is ignored.

Binhex: A file format used to encode Macintosh binary files as text files for easier transfer between computers. Binhex files usually have the suffix ".hqx". Almost all Macintosh communication programs will automatically detect and translate files in Binhex format. A special program called PCBINHEX may be used to translate text files to binary files for a PC.

BIOS: Basic In/Out System. Part of an IBM or compatible computer than manages the flow of signals through the hardware.

Bit: Binary digit. Smallest unit of digital information, either on or off, or 1 or 0.

Bitmap: An image stored as a pattern of dots (or pixels).

Boolean Logic: Rules and concepts for comparing data conditions including "less than," "greater than," "equal to," "and," "or," or "not." Used often to specify the conditions of a search on a large set of data.

Boot: The process of loading the operating system and starting of initial processes into a computer. The saying "pulling oneself up by one's bootstraps" is considered by many to be the origin of this term.

Bps: Bits Per Second. Speed at which data is transferred. Often used when discussing the speed of modems and serial transmissions.

Buffer: A temporary storage place for data during the transfer of that data between the computer and a peripheral or between parts of a computer to prevent loss of information.

Bulletin Board System (BBS): Also known as newsgroups. Electronic bulletin boards are computers running software which allows people to post messages and access information, much like an actual bulletin board.

Bus: Part of a chip or circuit board designed to send and receive data. The bus on a computer's motherboard contains slots for expansion cards.

Byte: The amount of memory needed to specify one ASCII character (eight bits). Kilobytes (1000 bytes) and megabytes (1,000,000 bytes) are usually used in discussing the amount of memory a computer uses.

C: A programming language.

C++: An extension of the C programming language.

Cache: Random-access memory (RAM) set aside as a buffer between the CPU and either a hard disk or slower RAM. Memory in a cache can be accessed quickly, speeding up data flow.

Cascade: In Windows. A way of arranging open program windows on the desktop so that they overlap each other, while the title bar of each window remains visible.

Cascading Menu: Also called a hierarchical menu or submenu. A menu that is launched from a command on another menu. In Windows, a command that opens a cascading menu has a right arrow next to it.

CCITT: Comite Consultatif Internationale de Telegraphique et Telephonique. An international committee that sets communications standards. The V.32, V.32bis, V.42, etc standards for modem speed and compression are CCITT standards. CCITT has been replaced by the ITU.

CD-ROM: Compact Disk-Read Only Memory. Compact disks that contain programs or data. The data on CD-ROMs cannot be written to. CD-ROMs can hold over 600 MB of data.

Centronics Interface (cable): (See Parallel Interface.)

Character Set: A group of letters, numbers, and symbols that have some relationship in common. For example, the ASCII character set contains characters that make up the ASCII coding scheme.

Check Box: Found in graphical user interfaces (GUIs). A small square box that appears in a dialog box and can be selected or cleared. When the check box is selected, an X (or some other indicator) appears in the box. A check box represents an option that you can turn on and off.

CISC: Complex Instruction Set Computing. A CPU architecture in which a large number of instructions are hard coded into the chip. Many older CPUs are CISC chips, like the Motorola 680x0, the Intel 80x86, etc. The Pentium chips have some RISC like features, but are still basically CISC chips. Contrast with RISC.

CLI: (See Command Line Interface.)

Client: A computer using services or resources provided by a remote machine (the server). Often, communications software will have a separate version for the client, or guest, and the server, or host.

Clipboard: A temporary storage location used to transfer data between applications. Typically, you transfer data to the Clipboard by using an application's Copy or Cut command, and you insert data from the Clipboard by using the application's Paste command. In Windows, you use the Clipboard Viewer to view the contents of the Clipboard.

Cluster: A group of sectors on a disk. DOS allocates disk space to files in clusters.

CMOS: Complementary Metal Oxide Semiconductor. A small section of RAM used to hold certain hardware configuration parameters. While the contents of CMOS rarely fails, a weak battery can loose all information. For this reason it's a good idea to print out the setup information in the CMOS area in the event it gets wiped out.

Coaxial Cable: A type of cable that is commonly used in systems due to its insensitivity to noise interference. Coaxial cable is often used in Ethernet networks. Both thick (10Base5) and thin (10Base2) Ethernet cables are coaxial.

COBOL: Common Business-Oriented Language. A programming language that is most often used for business programs.

COM Port: Also called a serial port. A connection on a PC computer where you plug in a serial device cable, usually designated COM1 or COM2. Common serial devices are printers and modems. Serial ports are smaller than parallel ports and usually contain nine pins.

Command Line Interface (CLI): A way of accessing a computer by typing commands rather than selecting icons and menu items. (See GUI).

Command Line: Commands you type to run an application. You can type commands at an MS-DOS prompt or via the Run dialog box in Windows. Interfaces in which you type commands rather than choose them from a menu or graphical representation are often called command line interfaces.

Command Prompt: Usually refers to the MS-DOS prompt. The character or characters that appear at the beginning of the command line (usually "C:"), indicating that the computer is ready to receive input and that you are "logged on" to the C drive.

Compiler: A program that translates source code written in a particular programming language into computer-readable machine code that can be executed on its own.

Concentrator: A device that permits you to position machines closer together on the network cable than you could otherwise. If you use a twisted-pair cable, you need a concentrator.

CONFIG.SYS: A text file that DOS reads when booting which tells the computer about the configuration of the machine. CONFIG.SYS contains configuration commands that enable or disable system features, set limits on resources, and extend the operating system functionality by loading device drivers.

Control Characters: ASCII characters that do not print but give instructions to the computer. They are usually found in word processors or telecommunications programs.

Conventional Memory: In an IBM PC or compatible computer, up to the first 640K of memory in your computer. By default, MS-DOS uses only this memory to run programs.

Coprocessor: An additional processor chip that increases the computer's speed by handling specialized chores such as math or graphics. Pentium (and later) processors have the math coprocessor built into the main CPU chip.

CPU: Central Processing Unit. Refers either to the principle microchip that the computer is built around (such as the Pentium or 80486) or the box that houses the main components of the computer.

CRT: Cathode Ray Tube. A television-like video tube which is the main component in most monitors.

Cursor: Sometimes called a pointer. An icon on the screen that moves when the computer's mouse is moved and allows the user to "point" to a command or position on the screen.

CYMB: Cyan, Yellow, Magenta, and Black. A color model used for specifying the color of printed matter. This corresponds to the four colors of inks used in most color printers. (See also RGB and HLS, common models used to specify colors on monitors.)

Daemon: An agent program that runs continuously and provides resources to client systems on the network.

Daisy Chain: A method of connecting devices on a bus. On a daisy-chained bus, devices that do not request a signal respond to it by passing it on. The daisy chain scheme permits assignment of device priorities based on the electrical position of the device on the bus. (See SCSI.)

Database: A structured set of data, normally associated with software for access and manipulation of that data

DCA: Document Content Architecture. IBM's specifications for a standard word processing format. Not widely used.

Debugger: A program or part of a program which aids in locating and correcting errors (bugs) in program code. It is said that the original "bug" was a moth that found its way into an early computer and caused it to malfunction.

Default Button: In some dialog boxes, the command button that is selected automatically if you press Enter or Return. In most GIUs default buttons have a bold border around them.

Defragment: To make files contigious on your hard drive so that they load faster. Accomplished by the defrag.exe program in Windows (Start/programs/accessories/system tools/disk defragmentor).

Degauss: On monitors, a process that demagnetizes the metal components in the CRT, thus eliminating image distortion that can result from magnetic charges acquired by the components. Some new monitors degauss automatically whenever you turn on your monitor, and some have a degaussing button.

Desktop: The term for the background screen in most GUIs on which windows, icons, and dialog boxes appear.

Device: A component of the system's hardware configuration, such as a modem, printer, mouse, sound card, or disk drive.

Device Driver: Software that controls how a computer communicates with a device, such as a printer. For example, a printer driver translates information from the computer into information the printer can understand.

Dialog Box: Also called a panel in some GUIs. A small window that appears temporarily to request information or to alert you to a condition. Dialog boxes usually request a response such as OK to continue or Cancel to stop an operation.

DIMM: Dual Inline Memory Module. A type of pre-assembled RAM unit used in some computers. DIMMs support a wider data path than SIMMs, allowing faster memory access.

Dimmed: A term usually used in GUIs to indicate that a particular command is not available or is disabled. Also sometimes know as "grayed out."

DIP Switch: Dual Inline Package. Small on-off switches mounted in computer hardware for purposes of user configuration. When adding expansion cards to computers, DIP switches must often be set to make the card compatible with the computer's configuration.

Direction Keys: Also called Arrow or Cursor Keys. Keys used at times to navigate around the screen and often used in text areas. Direction keys have arrows pointing up, down, right, and left.

Directory: Part of a structure for organizing your files on a disk. A directory can contain files and other directories (called subdirectories). Directories are often referred to as folders on computers with GUIs.

Disk: A medium for storing information. Information stored on a disk remains there even when you turn your computer off, unlike information stored in RAM. A floppy disk can be inserted and removed from a floppy disk drive, whereas a hard disk is permanently mounted inside its drive.

Disk Cache: A portion of RAM set aside for temporarily holding information while the information is written to or read from a disk drive.

Disk Drive: The mechanism that holds and spins a disk, reading and writing data.

Dithered Color: A color produced by a pattern of differently colored dots that simulate the desired color. A solid color on one device (such as a 256-color monitor) may be a dithered color on another device. Also knows as nonsolid color.

DLL: Dynamic Link Library contracts Terminate and Stay Resident (TSR). Windows automatically loads the applications into memory when required and unloads them when space is needed for other applications. Using this method, a programmer can depend on a common library of routines rather than reinventing them for each program.

Document: A data file. Whatever you create with an application, including information you type, edit, view, or save. A document may be a business report, a picture, or a letter and is stored as a file on a disk.

Document Window: In most GUIs, a window within an application window. There can be more than one document window open at a time.

Domain: Part of the IP address used to identify the organization or local network that a local host is connected to. For example: msn.com.

DOS: (See MS-DOS.)

Double-click: Clicking a mouse button twice in quick succession. Used in most GUIs to "open" a file or program.

Download: To transfer data or code from one computer to another. The distinction between downloading and uploading is hazy, but downloading often refers to a transfer from a larger server system (especially a mainframe computer) to a smaller client system like a microcomputer or specialized peripheral.

Downloadable Font: (See Soft Font.)

DPI: Dots Per Inch. Used in discussing the density with which a printer can print or a monitor can display an item. Describes the size of the pixels or dots of ink.

Drag: An action performed using a mouse. Used to move icons on the screen and to select commands from menus. Position the cursor on an item, press and hold the mouse button, move the cursor to a new location (by sliding the mouse), and then release the mouse button.

Drive Letter: The letter assigned to a drive on an IBM PC or compatible computer (for example, the letters A and B usually refer to floppy drives and C to a hard drive.)

EIDE: Enhanced Integrated Drive Electronics. A newer version of the Integrated Drive Electronics (IDE) standard for hard drives.

EISA: Extended Industry Standard Architecture. A bus standard for IBM PC and compatible computers that extends the AT bus to 32 bits.

Electronic Mail (Email): A method of transferring information (often text messages) from one computer to another over a network.

EMS: (See Expanded Memory Specification.)

Emulation: A process by which a computer imitates the actions of another computer. The imitating system accepts the same data and executes the same computer programs as the imitated system.

Emulation Mode: A special mode in which a device such as a printer can emulate the actions of a different device. Communications programs commonly emulate terminals.

Environment Variable: Environment information, such as a drive, path, or filename, associated with a symbolic name that can be used by MS-DOS. You use the MS-DOS SET command to define environment variables.

EPROM: Erasable Programmable Read-Only Memory. A computer chip that can be erased and written to but which will not lose its information when the computer is turned off.

ESDI: Enhanced Small-Device Interface. One type of hard drive specification for PC's.

Ethernet: A popular networking technology featuring 10Mbps transmission speeds running over thin coaxial (10Base-2), thick coaxial (10Base-5), or twisted pair (10Base-T) cables. Ethernet will support TCP/IP, Novell Netware, and other communication protocols.

Ethernet Address: An Ethernet address is a six-part hexadecimal number in which a colon separates each part (for example, 8:0:20:1:2e:0). This number identifies that an Ethernet communications board is installed in a PC and that the PC is a member of the network. Each Ethernet board has, in theory, a unique number as provided by the vendor in the board's firmware.

Expanded Memory (EMS): Memory beyond the 640K limit of usable RAM in DOS that conforms to the Lotus-Intel-Microsoft (LIM) specifications for expanded memory. This memory is available only to DOS applications that can support it. It is an older standard that is being replaced by extended memory.

Extended Memory: In an IBM or compatible PC, the memory above the 1Mb address range. Uses XMS (extended memory specification).

Extended Memory Manager: On an IBM PC or compatible computer, a program that prevents different applications from using the same part of extended memory at the same time.

Extension: The period (.) and up to three characters at the end of a filename. An extension usually identifies the kind of information a file contains. For example, text files often have the extension ".txt". Derived from the MS-DOS operating system but the convention is often used in other operating systems to help quickly determine the file type.

FAT: File Allocation Table. A special file in which MS-DOS stores information on the layout of a disk. This file is critical; if it is damaged, it is extremely difficult to get information from the disk.

FAX/Data Modem: Modems that can handle FAX protocols and also transmit data. Some older modems can only either send faxes or receive them; most can do both.

File: A program, document, utility, or anything that isn't hardware on a computer. A file might contain a memo, a drawing done in a graphics application, or a program itself.

File Server: A computer that provides networked computers with access to shareable resources. A dedicated file server can be used only as a file server while it is on the network. A non-dedicated file server can be used simultaneously as a file server and a workstation.

File Sharing: Provisions in the networking system software which allow more than one user to access the same file.

Firmware: Programs written permanently into read-only memory (ROM) chips.

Fixed Disk: (See Hard Disk.)

Fixed-Width Font: Also called a monospaced font. A font in which all characters have uniform widths, such as Courier. (See Proportional Font.)

Floppy Disk: A disk covered with protective packaging that can be removed from its drive. Currently, floppy disks are generally 3.5 inches wide. The protective covering on 3.5" disks is made of hard plastic that creates the false impression that these are hard disks. The media inside is the same floppy material as that inside the older 5.25" disks. Floppy disks are noted for their relatively slow speed, small capacity, and low price.

Flow Control: Also called handshake. The processes used to regulate the rate at which information is transferred from one device to another. One device sends a signal to the other when information can be transferred.

Folder: A graphical representation of a directory or subdirectory.

Font: A set of letters, numbers, punctuation marks, and symbols that is a given size and design. Some fonts can be scaled to any size while others are a fixed size. Outline fonts, TrueType fonts and PostScript fonts are examples of scaleable fonts.

Font Cartridge: A font contained in a cartridge that physically plugs into your printer.

Font Family: A group designation that describes the general look of a font. For example, the Roman font family contains proportionately spaced fonts with serifs.

Font Size: (See point size.)

Footer: Text that appears at the bottom of document pages when they are printed. (See Header.)

Foreground: The area of the screen occupied by the active window. (See Background.)

Format: Preparing a disk for use by your hardware and operating system. Also called initializing. When the computer formats a disk, it also destroys any information already on the disk (just as recording new sounds on a cassette tape replaces what was previously there). Formatting also refers to the way text is set up on a page (underlined, bold, indented, etc.) The term also stands for the way information is structured in a file, often specific to a particular application.

FPU: (See Floating Point Unit.)

Freeware: Software that is provided without charge. (See Shareware.)

FTP: File Transfer Protocol. Allows users to copy files between the local system and any system reachable over the network. Every UNIX system has FTP and there are versions for the Macintosh and Windows. A common way to make software (text files, sounds, pictures, utilities, etc.) available is to put it on an anonymous FTP server. Anonymous FTP servers allow users to login without a password, specify "guest" as the user, and then copy whatever is available.