: It is frequently used as a default name in "File Manager" directories on USB drives for generic song or meeting recordings (e.g., B_001.mp4 , B_002.mp4 ).
: MP4 (MPEG-4 Part 14) is a standard container for audio, video, and text. b_001.mp4
Could you clarify if you found this file on a , a work-related site , or a media server so I can provide more specific details? : It is frequently used as a default
