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A

ACL Access Control List
An ACL is a list of user permissions for a file, folder, or other object. It defines what users and groups can access the object and what operations they can perform. These operations typically include read, write, and execute. For example, if an ACL specifies read-only access for a specific user of a file, that user will be able open the file, but cannot write to it or run the file.

Access control lists provide a straightforward method of managing file and folder permissions. They are used by most operating systems, including Windows, Mac, and Unix systems. While ACLs are typically hidden from the user, they can often be modified using a graphical interface. For example, in Mac OS X 10.5, ACL settings can be edited by selecting a file or folder and choosing “Get Info.” The access control settings can be modified within the “Sharing and Permissions” section of the window. On Unix systems, ACLs can be edited using the chmod() command.

AGP Accelerated Graphics Port
Used exclusivly for graphics cards and are set back and keyed differently so that other expansion cards will not fit in them.

Asic Application-Specific Integrated Circuit

AIFF Audio Interchange File Format
An audio format originally developed by Apple Computer for storing high-quality sampled audio data. AIFF files are similar to Windows WAVE files in both size and quality. Both AIFF and WAVE files can hold CD quality audio and therefore can be burned onto an audio CD. Though the AIFF format was created by Apple, audio programs on both the Mac and PC can typically read the files.

ANSI American National Standards Institute
ANSI’s primary goal is to enhance the global competitiveness of U.S. businesses and to improve the American quality of life by promoting and facilitating voluntary consensus standards and conformity assessment systems. “Voluntary” standards are driven by marketplace needs rather than regulated by the government. “Conformity assessment systems” test the compliance of a product or service to a standard. ANSI does not itself develop standards or conduct tests, rather it facilitates this work by “accrediting” (i.e., recognizing) qualified groups with appropriate expertise. The Institute is the official U.S. representative to the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). ANSI is a private, nonprofit membership organization with offices in Washington, DC and New York City.

If you’d like more information about ANSI, there’s no better place to visit than ANSI’s Web site. There you’ll find more information about ANSI and what they do, as well as the latest news on national and international standards.

API Application Program Interface
Sometimes referred to as an “Application Programming Interface.” An API is a set of commands, functions, and protocols which programmers can use when building software for a specific operating system. The API allows programmers to use predefined functions to interact with the operating system, instead of writing them from scratch.

All computer operating systems, such as Windows, Unix, and the Mac OS, provide an application program interface for programmers. APIs are also used by video game consoles and other hardware devices that can run software programs. While the API makes the programmer’s job easier, it also benefits the end user, since it ensures all programs using the same API will have a similar user interface.

B

BIOS Basic Input/Output System
Built-in software that determines what a computer can do without accessing programs from a disk. On PCs, the BIOS contains all the code required to control the keyboard, display screen, disk drives, serial communications, and a number of miscellaneous functions.

The BIOS is typically placed in a ROM chip that comes with the computer (it is often called a ROM BIOS). This ensures that the BIOS will always be available and will not be damaged by disk failures. It also makes it possible for a computer to boot itself. Because RAM is faster than ROM, though, many computer manufacturers design systems so that the BIOS is copied from ROM to RAM each time the computer is booted. This is known as shadowing.

Bus Mastering
Allows for peripherals to directly communicate to each other without the help of the CPU. This often results in higher performance as well as less CPU utilization.

C

ccTLD country code Top-Level Domain
Typically a two-letter domain name extension, such as .uk, .us or .de, that corresponds to a country, territory or geographic location.

CIDR Classless Inter-Domain Routing
An IP addressing scheme that replaces the older system based on classes A, B, and C. With CIDR, a single IP address can be used to designate many unique IP addresses. A CIDR IP address looks like a normal IP address except that it ends with a slash followed by a number, called the IP network prefix. For example:

172.200.0.0/16

The IP network prefix specifies how many addresses are covered by the CIDR address, with lower numbers covering more addresses. An IP network prefix of /12, for example, can be used to address 1,048,576 former Class C addresses.

CIDR addresses reduce the size of routing tables and make more IP addresses available within organizations.

CIFS Common Internet File System
A protocol that defines a standard for remote file access using millions of computers at a time. With CIFS, users with different platforms and computers can share files without having to install new software.

CIFS runs over TCP/IP but uses the SMB (Server Message Block) protocol found in Microsoft Windows for file and printer access; therefore, CIFS will allow all applications, not just Web browsers, to open and share files across the Internet.

With CIFS, changes made to a file are simultaneously saved on both the client and server side.

CNAME Canonical Name
A record in a DNS database that indicates the true, or canonical, host name of a computer that its aliases are associated with. A computer hosting a Web site must have an IP address in order to be connected to the World Wide Web. The DNS resolves the computer’s domain name to its IP address, but sometimes more than one domain name resolves to the same IP address, and this is where the CNAME is useful. A machine can have an unlimited number of CNAME aliases, but a separate CNAME record must be in the database for each alias.

D

DDR Double Data Rate
A type of Synchronous DRAM, or SDRAM. DDR SDRAM enables data transfers to occur on both edges of the clock cycle, thus doubling the memory throughput of the chip.

DHCP Dynamic Host Configuration Protocol
A network server uses this protocol to dynamically assign IP addresses to networked computers. The DHCP server waits for a computer to connect to it, then assigns it an IP address from a master list stored on the server. DHCP helps in setting up large networks, since IP addresses don’t have to be manually assigned to each computer on the network.

DBMS Database Management System
A DBMS is a database program. Technically speaking, it is a software system that uses a standard method of cataloging, retrieving, and running queries on data. The DBMS manages incoming data, organizes it, and provides ways for the data to be modified or extracted by users or other programs.

Some DBMS examples include MySQL, PostgreSQL, Microsoft Access, SQL Server, FileMaker, Oracle, RDBMS, dBASE, Clipper, and FoxPro. Since there are so many database management systems available, it is important for there to be a way for them to communicate with each other. For this reason, most database software comes with an Open Database Connectivity (ODBC) driver that allows the database to integrate with other databases. For example, common SQL statements such as SELECT and INSERT are translated from a program’s proprietary syntax into a syntax other databases can understand.

Some definitions provided courtesy of Tech Terms.