What is a Codec?

A codec is a computer program that encodes or decodes digital data - the word itself is short for “coder-decoder,” or “compressor-decompressor.” Codec programs are required for your media player to play your downloaded music and movies. Whether we know it or not, we use codecs every day. In fact, the most commonly known codec examples are MP3, WMA, RealVideo, RealAudio, DivX and XviD. It is simply a program that can read or write these files.

A codec will take the digital information i.e. video or audio, and encodes this information into a data stream, a signal for transmission, storage or encryption, or decodes it for playback or editing.

For example, an audio codec converts analog audio signals into digital signals for transmission or storage. A receiving device, such as a media player, then converts the digital signals back to analog using an audio decompressor, for playback. An example of this is the codecs used in the sound cards of personal computers. A video codec accomplishes the same task for video signals.

Codecs are also used in videoconferencing, streaming media and video editing applications.