Sheepskin [Noun.]

1. The skin of a sheep, especially when used to make parchment or in bookbinding.

2. (United States of America) A diploma.

3. The tanned skin of a sheep with the fleece left on, especially when used for clothing, rugs etcetera.

Radial Tree

A Radial tree, or radial map, is a method of displaying a tree structure or tree data structure in a way that expands outwards, radially. It is one of many ways to visually display a tree. With examples extending back to the early twentieth century. In use, it is a type of information graphic.