The format is a container that can hold multiple video, audio, and subtitle tracks.
Use a tool like MediaInfo or the ffprobe command to see the internal metadata (resolution, frame rate, audio tracks) without fully opening the video. 90eac71c5649883967e5a706b937f58c.mkv
Since the filename is a hash, it is often used by automated systems or private archives. You can verify what the file actually is using these methods: The format is a container that can hold
If you need to view the file on a device that doesn't support MKV (like some smart TVs or older mobile devices), you can convert it: you can convert it: