An MKV file is a video container format similar to the .AVI, .ASF, and .MOV formats. It supports several types of audio and video codecs and may include .SRT, .SSA, or .USF (Universal Subtitle Format) subtitles. MKV files also support VobSub subtitles from DVDs.
The Matroska video format has become popular in the anime fan-subbing community (where users create subtitles) since it supports multiple audio and subtitle tracks in the same file. DivX Player supports MKV files on both Mac and Windows systems. MKV files can also be played on Palm, Symbian, and Pocket PC mobile devices using the CorePlayer Mobile software.