Tetrahedra

I know all of you who see this picture think its magic, its not. It's a bunch of tetrahedra interlocked. A tetrahedron is a polyhedron with 4 triangles that meet at a specific points. A polyhedron is a three-dimensional figure that has flat faces, and straight edges. As my friend always tells me, "you learn something new every day". And thus your geometry lesson is over for the day.