Traditionally, recording directly to a "standard" MP4 was extremely risky; if your computer crashed or lost power before the recording finished, the entire file would be corrupted and unrecoverable. Key Feature: Fragmented MP4 (fMP4)

: Instead of requiring the file to be "finalized" at the end, fMP4 splits the video into smaller, independently decodable segments called "fragments". If a crash occurs, everything recorded up to that moment is preserved.

The most significant and interesting feature regarding modern MP4 usage is the introduction of , specifically within recording software like OBS Studio .

: Modern implementations, such as the OBS Hybrid MP4, support multiple video and audio tracks within a single file, which is useful for advanced broadcasting and debugging. Minor Caveats

This newer variant solves the "corruption risk" by changing how data is stored:

: Previously, users had to record in .mkv format (which is naturally crash-safe) and then "remux" it into .mp4 for compatibility with editors. fMP4 eliminates this extra step.