Polyhedron
A polyhedron is a 3dimensional (solid) figure with flat faces. Cubes and pyramids are polyhedrons. Each flat face is a polygon.
A polyhedron where all the faces are the same (congruent) is a regular polyhedron. There are only 5 regular polyhedrons.
Here are all of the regular polyhedrons:
tetrahedron 
cube 
octahedron 
icosahedron 
dodecahedron 
Here are the volumes and surface areas of the regular polyhedrons: (s is the length of a side)
 Surface area  Volume 
Exact  Approximate  Exact  Approximate 
tetrahedron 
(√3) s^{2}
 (1.732) s^{2} 
s^{3}
√2 12 
(0.11785) s^{3} 
cube  6 s^{2}   s^{3}  
octahedron  (2√3) s^{2}
 (3.464) s^{2}  s^{3}
√2 3  (0.4714) s^{3} 
icosahedron  (5√3) s^{2}  (8.660) s^{2 }  s^{3}
(15 + 5√5) 12  (2.1817) s^{3} 
dodecahedron  s^{2}
(3√25+10√5 )  (20.64558) s^{2}  s^{3}
(15 + 7√5) 4  (7.6631) s^{3} 
