Codecs & Compression
Container Format
The file format (like MP4 or MKV) that wraps compressed video, audio, subtitles, and metadata together — distinct from the codec itself.
A container is a box, not a compression method — MP4 and MKV can both hold identical H.264 video, for instance. MP4 offers broader device compatibility, while MKV supports more flexible multi-track audio and subtitle configurations, which is why it's popular for archiving.