If your query is strictly related to video files, the "MP4" standard is what you are dealing with:
If you are working with 3D graphics (like glTF assets), tutorials often show how to bring them into software like Adobe After Effects to render them directly out to a flat MP4 video. 🛠️ 2. GTY Tools and Specialized Software GTYmp4
It primarily stores video and audio but can also hold subtitles and still images. If your query is strictly related to video