XviD is a codec based on the MPEG-4 standard. The codec distorts colors but it has high definition in dynamic scenes. XviD is constantly updating because it is an open source codec and anyone who is interested can participate in the development of the program. Using XviD may be illegal in some countries because the compression methods used in MPEG-4 are patented.

AVI is a multimedia container that is very popular among PC and Mac users. The format was developed by Microsoft in 1992. Usually AVI is used as a video format but unlike other formats of that time, AVI may contain both audio and video data compressed with a use of different combinations of codecs. More often such video codecs as DivX and XVID are used with .avi files. For audio playback such codecs as MP3, AC3 and PCM are used. It is possible to play AVI files with Windows Media Player or other similar programs.