Hand-Rotatable (or simply "Rotatable") means the pedestal comes with a Lazy-Susan top which can be rotated by hand (i.e., no motor). We use top quality bearings which are routed into the rotatable top in order to conceal the majority of the bearing from view and offer a low profile swivel top.
As most three dimensional art pieces are created to be appreciated from all angles, incorporating a rotatable top on your desired pedestal affords you easy 360-degree views regardless of where you place your art (e.g., against a wall). In addition, allowing the viewer to interact with the piece by simply turning the rotatable top protects your art from fingerprints and smudges. [Some artistic media such as acrylic (a.k.a. "Lucite") can actually be affected by the natural oils of our fingers.]
And, of course, there are those pieces which practically demand to be rotated as the artist's intent is for your perception of the piece to change as the piece is turned. This is particularly true of many acrylic (a.k.a. "Lucite") pieces with embedded figures or "hollow backs" where the images can change (from concave to convex or positive to negative) with each partial rotation. Other works emphasize the feeling of motion (e.g., dancers, animals, athletes) which is heightened when the piece is rotated.
Motorized means the pedestal comes with a motorized top which rotates on its own at approximately 1 RPM (Revolution Per Minute).
Base only pedestals have no rotatable top whatsoever. Most people prefer the flexibility of being able to rotate their piece whether by motor or by hand. However, there are some definite advantages to "no rotation" as an option. If you are certain that you do not want your artwork turned (e.g., all the interest is in the front of the piece; it would hit a wall or other object if rotated; you'd like to choose the Overhead Halogen feature and the particular dimensions of your piece would not allow for wire clearance; you like the clean look of a simple top; you do not want to tempt curious visitors to spin your art) or your sculpture already has a built-in bearing on the bottom, then base only might be the right choice for you.