Glossary

A Record

    An A record is part of the zone file and is used to point Internet traffic to an IP address. For example, you can use an "A record" to designate abc.yourdomain.com to send traffic to your web site at IP address 209.132.X.XX. You can also designate xyz.yourdomain.com to go to a separate IP address.

ADSL

    (Asymmetric Digital Subscriber Line) -- A method for moving data over regular phone lines. An ADSL circuit is much faster than a regular phone connection, and the wires coming into the subscriber's premises are the same (copper) wires used for regular phone service. An ADSL circuit must be configured to connect two specific locations, similar to a leased line.

    A commonly discussed configuration of ADSL would allow a subscriber to receive data (download) at speeds of up to 1.544 megabits (not megabytes) per second, and to send (upload) data at speeds of 128 kilobits per second. Thus the 'Asymmetric' part of the acronym.

    Another commonly discussed configuration would be symmetrical: 384 kilobits per second in both directions. In theory ADSL allows download speeds of up to 9 megabits per second and upload speeds of up to 640 kilobits per second.
    ADSL is often discussed as an alternative to ISDN, allowing higher speeds in cases where the connection is always to the same place. See Also: bit , bps , ISDN

Anonymous FTP

Applet

    A small Java program that can be embedded in an HTML page. Applets differ from full-fledged Java applications in that they are not allowed to access certain resources on the local computer, such as files and serial devices (modems, printers, etc.), and are prohibited from communicating with most other computers across a network. The current rule is that an applet can only make an Internet connection to the computer from which the applet was sent. See Also: HTML , Java

Archie

    A tool (software) for finding files stored on anonymous FTP sites. You need to know the exact file name or a substring of it.

ARPANet

    (Advanced Research Projects Agency Network) -- The precursor to the Internet. Developed in the late 60's and early 70's by the US Department of Defense as an experiment in wide-area-networking that would survive a nuclear war.

ASCII

    (American Standard Code for Information Interchange) -- This is the de facto world-wide standard for the code numbers used by computers to represent all the upper and lower-case Latin letters, numbers, punctuation, etc. There are 128 standard ASCII codes each of which can be represented by a 7 digit binary number: 0000000 through 1111111.

Backbone

    A high-speed line or series of connections that forms a major pathway within a network. The term is relative as a backbone in a small network will likely be much smaller than many non-backbone lines in a large network. See Also: Network

Bandwidth

    How much stuff you can send through a connection. Usually measured in bits-per-second. A full page of English text is about 16,000 bits. A fast modem can move about 15,000 bits in one second. Full-motion full-screen video would require roughly 10,000,000 bits-per-second, depending on compression. See Also: Bps , Bit , T-1, OC-3.

Baud

    In common usage the baud rate of a modem is how many bits it can send or receive per second. Technically, baud is the number of times per second that the carrier signal shifts value - for example a 1200 bit-per-second modem actually runs at 300 baud, but it moves 4 bits per baud (4 x 300 = 1200 bits per second). See Also: Bit , Modem.

Binhex

    (BINary HEXadecimal) -- A method for converting non-text files (non-ASCII) into ASCII. This is needed because Internet e-mail can only handle ASCII. See Also: ASCII , MIME , UUENCODE

Bit

    (Binary DigIT) -- A single digit number in base-2, in other words, either a 1 or a zero. The smallest unit of computerized data. Bandwidth is usually measured in bits-per-second. See Also: Bandwidth , Bps , Byte , Kilobyte , Megabyte .

Bps

    (Bits-Per-Second) -- A measurement of how fast data is moved from one place to another. A 28.8 modem can move 28,800 bits per second. See Also: Bandwidth , Bit

Browser

BTW

    (By The Way) -- A shorthand appended to a comment written in an online forum. See Also: IMHO , TTFN

Byte

    A set of Bits that represent a single character. Usually there are 8 Bits in a Byte, sometimes more, depending on how the measurement is being made. See Also: Bit

Certificate Authority

CGI

    (Common Gateway Interface) -- A set of rules that describe how a Web Server communicates with another piece of software on the same machine, and how the other piece of software (the 'CGI program') talks to the web server. Any piece of software can be a CGI program if it handles input and output according to the CGI standard.

    Usually a CGI program is a small program that takes data from a web server and does something with it, like putting the content of a form into an e-mail message, or turning the data into a database query.
    You can often see that a CGI program is being used by seeing 'cgi-bin' in a URL, but not always. See Also: cgi-bin , Web

cgi-bin

    The most common name of a directory on a web server in which CGI programs are stored. The 'bin' part of 'cgi-bin' is a shorthand version of 'binary', because once upon a time, most programs were refered to as 'binaries'. In real life, most programs found in cgi-bin directories are text files -- scripts that are executed by binaries located elsewhere on the same machine. See Also: CGI