Cache
A cache is a system for storing frequently accessed information for faster response. Cache memory on your motherboard is extra-fast RAM that keeps a copy of the most recently requested bits from regular RAM. A 'caching proxy web server' keeps the most recently requested web documents stored locally, reducing response time from (often very slow) remote web sites.
CCITT
French acronym for the international standards organization. The "International Telegraph and Telephone Consultative Committee". Part of the United National International Telecommunications Union (ITU).
CC:Mail
A proprietary electronic mail processing system.
CD
Compact Disc, a standard for storing information on an optical media.
Chew
A component of network lag, chew is the percentage of packets that are 'eaten' by the network connection. Ideally no packets should be lost, but the Internet is often anything but ideal.
CID
Caller-ID, a system by which the calling-party number (and sometimes the name and called-number) is transmitted to the called party. Similar to, but less powerful than ANI.
CIDR
Classless interdomain routing, a technique supported by BGP-4 allowing routing routing between multiple independent networks, without the old notion of subnet 'classes' (e.g. Class 'C' network space).
CISC
Complex Instruction-Set Computer. A CPU designed with a thorough set of assembly calls, systems based on this philosophy have smaller binaries but generally slower execution of each individual instruction.
See also RISC.
Cisco
A major network equipment vendor, the name is derived from the city of San Francisco. The company is best known for it's routers and general high quality software and hardware.
CIX
The Commercial Internet Exchange is a trade association of internet connectivity providers.
client
A client connects to a server, with which it exchanges information.
See also: X-window.
Coax
A cable with a single inner conductor and outer shield, used primarily for certain ethernet standards and radio frequency (audio and video) transmission.
See also: twinax.
COE
The Component Object Model, the fundamental class of Microsoft's attempt to defuse the growth of Java platform-independent code.
Cookie
A piece of data given to your browser by a web server, so that your browser will hand it back to the server with subsequent requests. First implemented by Netscape. Although there has been some furor over the privacy implications of cookies, they cannot be used to reveal anything about you to the server that you have not already explicitly revealed. (rebecca)
Compress
To make a file smaller by applying a compression algorithm, usually for the purpose of conserving space or speeding up file transfers. This can also refer to the Unix command to compress a file which appends '.Z' to the filename, '.gz' or to the free GNU enhanced version, gzip.
CPE
Customer Premise Equipment. On digital circuits provided by the telephone company, any terminating hardware owned by the user and not by the telco is generically referred to as CPE.
CPU
Central Processing Unit. The part of a computer that executes commands and interfaces between the various devices and sub-processors.
CRC
Cyclic Redundancy Check, a simple checksum used for detecting errors.
Cross-Over
A cable or connection which reverses the transmit and receive signals, allowing the direct connection of two devices.
Cryptography
The study of codes, cryptography refers to the making and breaking of algorithms to conceal or otherwise encrypt information. One of the most popular internet encryption schemes is PGP.
CSU
Channel Service Unit, a hardware device used to interface between a serial port and a digital circuit, generally a device used to connect a digital circuit to a serial interface is a "CSU/DSU".
CTCP
An acronym for Client-To-Client-Protocol, a feature of some IRC clients.
cyber-
Deprecated. A prefix used by newbies and lamers to describe internet related topics, such as "cyberspace".