Quick guide
About MKV and MP3 files
MKV - Matroska Video
MKV is a flexible video container that can hold multiple audio tracks, subtitles, and chapters. It is common for high-quality video files and media collections.
MP3 - MPEG-1 Audio Layer III
MP3 is a compact audio format that works almost everywhere. It is a good choice when you want a small file for music, voice recordings, podcasts, or sharing audio online.