The Matroska Video File (MKV) is a flexible, open standard video file format, a container format that can hold an unlimited number of video, audio, picture, or subtitle tracks in one file. It is intended to serve as a universal format for storing common multimedia content, like movies or TV shows. MKV is similar in concept to other containers like AVI, MP4, or ASF, but is entirely open in specification, with implementations consisting primarily of open source software. The format supports features like multiple audio and subtitle tracks, chapter markers, and metadata, making it a versatile choice for archiving and distributing video content. Its open nature and robust feature set have made it a popular choice for both personal and professional use, especially in the realm of high-definition video. MKV files are often used for storing movies and TV shows downloaded from the internet, as they can contain multiple audio tracks in different languages and subtitles.