
QuickTime
That is the extra text in the Get Info window of the QuickTime extension under the Classic Mac OS.
All in all QuickTime has been pivotal for the industry. Windows users see it as a bloated 'player' and it may be on Windows, but in reality it has been the multimedia architecture for the nineties on the Mac. I think we haven't seen a lot of films over the past 2 decades that haven't gone through QuickTime in some way or the other.
And .mov being a proprietary container? IIRC the MPEG group has chosen the file format for the MPEG4 specification.