# Icosahedron

*Icosahedron* is one of only five Platonic solids. This is a regular polyhedron with 12 vertices, 30 edges, and 20 faces. All faces are regular triangles and at every vertex meet five faces and five edges.

Drag the mouse to rotate the icosahedron. Use the right button to remove and put back individual faces.

The word *icosahedron* originates with the Greek *eikosi* (20). The other Platonic solids are tetrahedron, octahedron, dodecahedron, cube. With 20 faces, 30 edges, and 12 vertices a icosahedron confirms to the Euler's theorem:

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