What Type Of Head?The classic tripod head is a two-way or three-way head, usually referred to as a pan-and-tilt-style head. These heads have handles to control the horizontal panning and vertical tilting. The third direction in a three-way head is flipping the camera on its side for portrait orientation shots.
Ballheads are preferred by many photographers for the ability to move smoothly on any axis. This type of head consists of a ball that holds the camera and is able to pan, tilt or twist in any direction. Not as easy to use as a pan-tilt-style head, you do get greater flexibility and a more compact form factor.
The other popular style, particularly for sports and nature photographers who use large telephotos, is the gimbal head. Like a ballhead, there are no handles to help guide the camera. The mounting plate on the lens is attached to the gimbal and freely pivots up and down, while the base can pan horizontally.
What type is likely to suit your needs? If you shoot video, either with a video camera or an SLR with video mode, you're best served by a pan-tilt head or the zero-gravity-style system from VariZoom. Both options give you the stable and smooth tracking that's critical for video use. The best video heads are fluid heads, which use a lubricant for the smoothest panning. Still photographers will appreciate the flexibility of a ballhead system, thanks to its more compact size and solid locking abilities for sharp exposures. If you need a one-head-does-all solution, the pan-tilt head will serve you best—if you've ever seen a shaky video, you'll understand why this needs to be the key feature.