Far as I know it originates with AC power and pre-NTSC (or PAL) TV systems that keyed on it. In the US, it cycles at 60hz, in a lot of EU countries 50hz, etc. While NTSC doesn't key on it, the signal was broadcast slightly off from that (hence why it's not quite 60 fields/30 frames per second) so that the legacy black and white signal could still be there.RCBH928 wrote:Whats the secret with 60 any way, why not 80 or 120 or 200?!
Computer monitors have done higher refresh rates for a long time though.
With respect to video itself, probably more just a matter of matching capability. The higher framerate that's being recorded, the more data (or film) needed, so you'd want a reason for that increased cost. So, it'd be used if the footage was intended to be slowed down, but otherwise you usually see higher framerate on content generated in real time (games, etc).