Meaning of "brand" in video file formats?

[Stephen Tashi]

TL;DR

What is the definition of "major brand" and "compatible brand" in the description of a video file?

The program ffmpeg can be run on a video file to print out information about the file format.
An example of some output:

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'Mid Air Engine Catastrophe - Air Crash investigation 2020 - Mayday Airplane Full documentary - Plane-_oKX1pcDt-E.mp4':
Metadata:
major_brand : mp42
minor_version : 0
compatible_brands: isommp42

What is the meaning of the brand information?

 

[scottdave]

I did some searching, and found this http://ftyps.com/ as well as some other links.

It appears the "brand" is another way of saying what format it is compatible with.