Orbital: The oscillating movement of an orbital buffer produces much less heat on the paint's surface and therefore is much more forgiving. The two most popular are the Porter Cable (PC) and the Orbital Flex.
Finally, the rotary buffer quickly builds up enormous heat because of its 360 degrees turning table and is the most efficient in end result and time for paint correction. Makita is one of many makes of rotaries, but certainly one of the most used within the industry. A good rotary is cheaper than a n orbital Flex, by about $100, but can do damage tenfold of the savings if not used properly.