Hi. OK, there are snatches, power snatches, and muscle or Hi Pull Snatches. Each can be done from either the floor, or the Hi hang, which is just above the knee, or the Low Hange, in which you lower the bar to just below the knee, approx mid shin level.
The Snatch, well, you would want a standar wide grip, to make pulling distance shorter. The same with the power snatch. The only difference between these two, is that in the full snatch, youjump down under the bar into a full overhead squat position. With the Power snatch, you dip down only into a half to a quarter squat postion.
The Muscle/Hi Pull Snatch, well, this is the one I think you saw. Grip width doesn't matter that much, as you are going for a pull all the way up. The narrowest I've ever done it is with a shoulder widh grip, but it can be anywhere from wide to shoulder width. It starts out the same as the other two, but where it differs is there is no dipping, or bending of the knee, you just grip it, rip it up as high as you can, turn the wrists up for the catch, and if necessary, finish with pressout. I like it for conditioning work, as it really doesn't take a lot of technique, and it's much easier (for me anyway) to do more reps. Same thing with DB or KB 1 arm swings or snatches.