A Computer Glossary For the New York Farm Viability Institute Computer Training Courses 2006
GLOSSARY This Glossary is primarily applicable to DOS- and Windows-based machines and applications. Address: The coded portion of a disk sector that stores the location of data in an electronic table that lists all of the data addresses on that disk. Application Program: A computer program used to perform a specific task, such as word processing, spreadsheet creation, or database management. ASCII: Acronym for American Standard Code for Information Interchange. A standard set of characters used to enable compatibility between different computer devices. Back Up: The process of making duplicate copies of files, disks, or directories for safekeeping in case of data/file loss. Batch File: A file that contains a series of DOS commands that execute automatically. Booster Keys: Keys that do not perform actions by themselves but can be used with other keys to issue commands. The booster keys are Ctrl, Alt, and Shift. Boot: To start a computer and load the operating system into RAM. See also Reboot. Byte: The basic unit that measures memory and disk storage capacity. Generally, one byte represents one character. Central Processing Unit (CPU) The part of a computer that interprets and executes instructions. Chip: An integrated electronic circuit consisting of miniature transistors and other circuit elements contained on a silicon wafer. Cold Boot: To start a computer and load the operating system into RAM. See also Reboot. 2
Command: An instruction for DOS to perform a specific action. Command Line Help: Help that can be accessed by typing a command name followed by the /? Switch. Command Name: The component of a command that specifies what action DOS is to perform. Computer: An electronic device capable of storing, retrieving, and manipulating information. Computer System: A collection of computer-related devices used to input, manipulate, and display output data. Current Directory: The directory that DOS is currently using. See also Directory and Subdirectory. Current Drive: The disk drive that DOS is currently using. See also Disk Drive. Cursor: A symbol on the screen that marks the location where characters will appear as they are typed from the keyboard. The cursor usually displays as a blinking vertical line in a word processor or as a blinking underscore. Data: Information, usually in the form of alphanumeric characters. Database: An electronic file used to store and organize data. Data Disk: A disk that contains data created with an application program. Data File: A file that contains data to be used with an application program. Default: An assumed value or option the computer uses when none is specified. Synonomous with regular, normal, or primary (as in a printer). Or as in normal or standard settings in an application or software program. Default in computers has NOTHING to do with finances. 3
Density: The data storage capacity of a disk. See also Double-Density and High-Density. Directory: An area on a disk where you store a group of related files under an identifying name. Also a list of files contained on a disk. See also Subdirectory. Disk: A circular platter with a magnetic coating on both sides. The most common medium for storing computer data. See also Diskette and Hard Disk. Disk Drive: A mechanism that reads and writes data on a disk. Diskette: A removable computer storage medium made of plastic and covered with a magnetic coating. Usually 3_ in size (5_ floppy diskettes are obsolete). See also Disk and Hard Disk. Disk Operating System (DOS): The name used for various operating systems. The primary function of a disk operating system is to control the flow of data to and from the CPU and peripherals. Double-Density: The diskette type that holds 720 Kb of data in 3_ diskettes (360 Kb of data in obsolete 5_ diskettes). Drive: A mechanism that reads and writes data on a disk. Drive Head: The part of a disk drive that reads and writes data. Error Message: An on-screen message resulting from an invalid command from the user or an internal system failure. Extension: The optional part of a filename often used by DOS-based systems to indicate the file type. An extension can contain up to three characters. External Commands: Commands stored in program files on a disk, which can only be executed when the program file is present in the current directory or in a directory, specified in a path statement. 4
File: A collection of related data stored on a disk. Filename: An identifying name under which DOS stores a file on a disk. A filename can contain up to 255 characters and an optional three-character extension. Characters NOT allowed: @, #, $, %, &, *, / (forward slash), or \ (backward slash) See also File and Extension. Fixed Disk A large capacity storage medium for computer data. See also Disk and Diskette. Floppy Disk: A removable computer storage medium made of plastic and covered with a magnetic coating. Usually 3_ in size (5_ floppy diskettes are obsolete). See also Disk and Hard Disk. Folder: A named area on a disk drive used to store or organize files or documents, similar to a manilla folder that is used to store hard copies of files or documents. Also sometimes referred to as a directory. Format: (Dual meaning) a) To prepare a disk (or Drive) for data storage by creating sectors and cleaning (erasing) any and all files. b) The layout or appearance of a document in terms of fonts, margins, etc. A special formula will have a certain format (sometimes also referred to as syntax), or appearance. Hard Disk: A large built-in storage capacity medium for computer data. See also Disk and Diskette. Hard Drive: A large built-in storage capacity medium for computer data. See also Disk and Diskette. Hardware: Any of the mechanical or electrical components of a computer such as the CPU, memory chips, disk drives, keyboard, and monitor. High-Density: The type of 3_ diskette that holds 1.44 Mb of data. Input: Any data entered into a computer for processing. Input Device: A mechanism, such as a keyboard or a mouse, used to give instructions to a computer for processing. See also Peripherals. 5
Internal Commands: Commands that are loaded into RAM with DOS when a computer is booted and which can be executed whenever the system prompt is displayed. Kb or K or Kilobyte: 1,024 bytes or characters. Keyboard: An assemblage of systematically arranged keys, which when pressed, input data into a computer. Lock Up: When a computer does not accept input from the keyboard or any other input device, and the cursor does not move. A computer that locks up may have to be restarted again. Mb or M or Megabyte: 1,024,000 bytes or characters. Memory: The internal electronic work space where data is stored. See also Random Access Memory (RAM) and Read-Only Memory (ROM). Menu: An on screen list of choices from which you select a command or an application. Microcomputer: A stand-alone computer system that typically fits on a desktop. Microprocessor: The part of a computer that interprets and executes instructions. Modem: Modulator-demodulator. A device that transmits data over a particular medium such as telephone lines or coaxial cables. Monitor: The visual display unit of a computer system. Mouse: A small, hand-held mechanism that controls the movement of the cursor or a pointer on a computer screen. MS Backup: A utility program used to back up a large number of files. See also Back Up. 6
Output: Data that is generated from a computer after processing. Output Device: A mechanism, such as a printer or a monitor, used to retrieve and view data after it has been processed by a computer. Parameters: Components of a command that specify where, or on what, an action is to be performed. Parent Folder or Directory: A directory that contains files or subdirectories. See also Directory and Subdirectory. Peripherals: Additional components which enhance computer performance. Power On Self Test: A series of tests performed by a computer when it is turned on. Printer: A device for generating computer output on paper. Program: A set of instructions that a computer follows to perform a task. Program Disk: A disk that contains application programs such as a word processing program or a spreadsheet program. Program File: A file that contains instructions used by a computer. Random Access Memory (RAM): Temporary memory that holds application programs and data which you create and manipulate. Read-Only Memory (ROM): Permanent memory that hold the programs which are responsible for the initial phases of starting a computer. Reboot: To restart a computer by turning it off and then on again by pressing Ctrl, Alt, Del, or by pressing a reset button. See also Boot. Sector: A part of the track on a disk where data is stored. See also Track. 7
Software: Any set of instructions or data a computer may use. The programs that tell a computer what to do and how to do it. Spreadsheet An electronic grid of rows and columns used to enter, organize and analyze a collection of numbers or data. Subdirectory or Subfolder: A directory that is contained within or is subordinate to another directory. See also Directory. System Disk: A disk that contains the DOS startup programs used to boot a computer and load DOS into RAM. Track: Concentric circles on the surface of a disk. See also Sector. Volume Label A name that is electronically assigned to a disk. Warm Boot: To restart a computer by turning it off and then on again by pressing Ctrl, Alt, Del; or by pressing a reset button; or by choosing Restart from the Start/Shut Down menu. See also Boot. Skips the POST test. Wildcard Characters: Special characters that can be used in most DOS commands as substitutes for other characters. The asterisk (*) and the question mark (?) symbols are wildcard characters. Word Processor: The software used to create, edit, and print text documents such as letters or memos. Write-Protect: To prevent data on a diskette from being erased or overwritten. 8