MP4, formally known as MPEG-4 Part 14, is the most widely supported digital multimedia container format for storing video, audio, subtitles, and metadata in a single file. In live streaming contexts, MP4 is commonly used for recording and archiving live streams for on-demand playback after the live event concludes. It is universally supported across browsers, mobile devices, and media players, making it the standard format for distributing recorded video content derived from live streams.