（单词翻译:单击）
Cache - Generally, a place to temporarily store something. Regarding computers and telecommunications, it is a place where data is temporarily stored during transmission.
Call - This is a connection between two or more users with the intent of exchanging information.
Call Back - This is a security method with which a user calls into a system and requests to be called back by the system at a particular, predetermined number.
Caller - Anyone who makes a call.
Caller ID - The service that allows someone being called to see the caller's name and phone number.
Call Progress - This is the status of the telephone line. It can be busy, ringing, not ringing, etc.
Call Waiting - This is a service that tells you if someone is trying to call you when you are already using the line (i.e., talking with someone else).
Capacitor - This is an electronic device for storing electric charge.
Capture Effect - This effect occurs when two signals are received that are the same (or nearly the same) frequency. The stronger signal will appear in the output.
C-Band - The portion of the electromagnetic spectrum1 allotted2 for satellite transmission; it is the 4 to 8 GHz frequency transmission range. Specifically, the 3.7 to 4.2 GHz band is used as the downlink, and the 5.925 to 6.425 GHz band serves as the uplink.
Card - This term refers to a computer peripheral3 that can be connected internally (i.e., directly), without any cables, to a computer, such as a modem4.
Caret5 - This is the character "^".
Carrier - This term refers to: (1) a company, such as a local telephone company, that provides circuits dedicated6 to communication, and (2) an electrical signal capable of being modulated7 to carry information.
Carrier Detect (CD) - This is a light on most modems8 that signifies, when lit, that the modem is connected.
Carrier Frequency - The main frequency on which data, a voice, or video signal is sent. Common microwave and satellite communications transmitters operate in the band from one to fourteen GHz.
Carrier Signal - The basic radio, television, or telephony center of a frequency transmission signal.
