1. What is codec

A codec is a shortened version of the term "compressor/decompressor" and it is specially applied to the wide variety of algorithms and their implementation used for the compression or decompression of audio and video information.

A multimedia codec will normally include audio compression and decompression algorithms, video compression and decompression algorithms and these may be implemented in either software on the

host computer or in special hardware attached to it and designed to speed up the algorithms. These algorithms are used in order to eliminate the time delay in transferring the message and also in reducing the overall bandwidth required for a given application. The audio and video data will be compressed before being sent and, at the other end, the received audio and video data should be extracted (decompressed) before being played back. For details please see Multimedia Codecs.