Usually a lack of legs or skirt means that the furniture has a swivel base, a reclining mechanism, or casters, but there are some design applications that are upholstered to the floor purely for aesthetic reasons. These tend to be more casual designs.
A band of fabric that runs around the entire base of the furniture, attached only at the top of the skirt and extending to the floor to conceal the legs. Used only in traditional styles, and not available in leather furniture.
Legs that are rounded or carved into ornate designs, these can be relatively short (called "bun feet") or quite long and decorative. This design tends to be used on more formal or traditional pieces.
Legs that have straight sides and distinct corners (though they are usually slightly rounded to avoid unnecessarily sharp edges). These may be relatively short (called "block feet") or very long and slender. Tapered legs tend to be used in more contemporary designs.