The art of topiary entails the pruning of live shrubs or trees into decorative shapes, as of animals. Not only is the art form called "topiary," but the results of such pruning are also known as "topiaries."
English boxwood shrubs are commonly used in topiary, due to their amenability to pruning, their rounded growth habit and their slow growth rate.
Boxwoods are also often used in another kind of "topiary." In this kind of topiary, it's not live plants that are used, but cut branches. The branches are inserted in styrofoam or in Florist's foam and arranged according to the shape one desires. For instance, at Christmas, "boxwood Christmas trees" are popular -- i.e., topiary arrangements in Christmas-tree shape made with sprigs of boxwood. For preservation, these arrangements must be misted often.
