Is a regular polyhedron a pyramid?

There are five regular polyhedra, also known as the Platonic solids. They are three-dimensional shapes where all of the faces are made up of the same regular polygon.

They are:

• Tetrahedron with four faces (this one is like a pyramid, but with an equilateral triangle for the base and all of the faces)
• Cube with six faces (all squares)
• Octahedron with eight faces (all equilateral triangles)
• Dodecahedron with 12 faces (all regular pentagons)
• Icosahedron with 20 faces (all equilateral triangles)

A square pyramid (like the Egyptian pyramids) is not a regular polyhedron, because it has two different types of regular polygons for faces.