In addition to Raven's comments: Pan: horizontal motion, for tracking objects moving in a horizontal line, like a car moving over the road. Tilt: Vertical motion, like following an elevator Mine also has an option of setting the camera on it's side in portrait mode. On a ball head you can basically set it in any direction and do that using only one screw, on the pan/tilt model you'll have to use at least 2. Downside to that is unsteadyness if you need to track like with a pan. Also getting it perfectly horizontal may be a bitch.

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