Gestures in QuickTime Player
In addition to system-wide gestures, there are some that only work in specific apps. In QuickTime Player, drag two fingers from left to right across the trackpad to scrub forwards through video. To return to normal speed, just lift your fingers from the trackpad. Drag two fingers from right to left to scrub backwards. The further across the trackpad you drag, the faster the video will scrub. To enter full-screen mode, spread two fingers across the trackpad. To leave full-screen, pinch with two fingers.