MP4 (MPEG-4 Part 14) is a digital multimedia container format most commonly used to store video and audio. Unlike simple audio formats like MP3, MP4 is highly versatile, capable of housing:
Including subtitles (Timed Text), still images, and complex metadata. Bitrates and File Identifiers
In professional cinematography, numbers associated with the "mp4" extension often indicate the quality of the capture. For instance, many high-definition cameras use a setting for recording in MP4 format, which strikes a balance between professional-grade visual fidelity and manageable file sizes.