They are geometrical forms which are said to act as a template from which all life springs. The aesthetic beauty and symmetry of the Platonic solids have made them a favorite subject of geometers for thousands of years. They are named after the ancient Greek philosopher Plato who theorized that the classical elements were constructed from the regular solids. To the Greeks, these solids symbolized fire, earth, air, spirit (or ether) and water.
http://en.wikipedia.org/wiki/Platonic_solid In Euclidean geometry, a Platonic solid is a regular, convex polyhedron with congruent faces of regular polygons and the same number of faces meeting at each vertex. Five solids meet those criteria, and each is named after its number of faces.