backslash (\)
Symbol used to separate each directory level, for instance C:\Windows\Utilities. For this reason, it is a reserved character and cannot be used as part of a filename.
bandwidth
Used in several ways to denote the amount of data or load capacity of a medium. 1) The range of frequencies that an electronic system can transmit. High bandwidth allows fast transmission or the ability to transmit many signals at once. 2) On a monitor screen, a higher bandwidth that provides a sharper image. 3) The rate at which data can be send over a modem or other telecommunication device.
battery
A power source for use outside or as an alternate to the electrical mains. Prevents unique information about the setup of the computer from being lost when the power is turned off. Also maintains the external clock time (not to be confused with the CPU's clock).
baud
Roughly speaking, a measurement of how fast data can be sent over telephone lines.
BBS (bulletin board system)
A local computer system that is not part of the Internet. It allows users to dial in and chat with others and download or upload files.
binary file
A file type in the form of pure data (1s and 0s) that needs to be converted to image, sound, or application to be used. Contrast this to an ASCII file.
binary system
The language used by computers-it is based on something being either on or off. There are only two digits used in binary language; 1 equals on and 0 equals off.
BIOS (basic input/output system)
Software that includes hundreds of little programs stored on ROM chips, used during the startup routine to check out the system and prepare to run the hardware.
bit
The smallest unit of information that is recognized by a microcomputer. Shorthand term for binary digit. There are only two possible binary digits: 0 and 1.
Bi-Tronics
A modified Centronics connection created by Hewlett-Packard. It utilizes bidirectional communication, allowing the printer to send messages to the computer (out of paper, paper jam, and so forth).
BMP
A bitmapped graphics file native to the Windows environment.
boot partition
A hard-disk partition containing the portion of the operating system needed to launch the operating environment.
boot up
To start a computer; drawn from the phrase "pulling oneself up by one's own bootstraps."
bps (bits per second)
The speed at which a modem transmits data. Typical rates are 14,400, 28,800, 33,600 and 56,600 bps. This represents the actual number of data bits that can be transmitted per second.
bridge
A device that provides communication between two or more network segments, thereby forming one logical network.
broadband
A network with high bandwidth (greater than 256 bps).
browser
Software used to navigate the World Wide Web, such as Microsoft's Internet Explorer and Netscape Navigator.
bus
The main communication avenue in a computer. It consists of a set of parallel wires that are connected to the CPU, memory, and all input/output devices. The bus can transmit data in either direction between any two components. If a computer did not have a bus, it would need separate wires to connect all the components.
bus mastering
The ability of a device to control its own data bus, only making use of the main system bus when data must be sent to the CPU or another device. This reduces CPU and system bus traffic, improving overall performance.
bus network
A network in which all computers are connected to a single linear cable. Both ends of the cable must be terminated. Because there is no central point, it is harder to isolate problems in a bus network than in a star network topology.
byte
A group of 8 bits that represents 1 character of information (for instance, pressing one key on the keyboard). A byte is the standard unit of measuring memory in a microprocessor. Memory size is measured in terms of kilobytes (KB) or megabytes (MB). 1 KB of RAM is 1024 bytes; 1 MB is approximately one million bytes.