A polyhedron (one polyhedron, many polyhedra, or polyhedrons) is a geometrical shape. It has flat faces, and straight edges. Usually it is defined by the number of faces, or edges.
Mathematicians do not agree on what makes a polyhedron. They do agree that there are five Platonic solids.
Naming[change | change source]
Usually, polyhedra are named by the number of faces they have. The first polyhedra are the tetrahedron, which is made of four triangles, pentahedron (five faces, can look like a four-sided pyramid), hexahedron (six faces, a cube if it is regular), and heptahedron (seven faces, can look like a prism based on a pentagon, or a pyramid based on a hexagon amongst others).
Other websites[change | change source]
- Eric W. Weisstein, Polyhedron at MathWorld.
- Making Polyhedra
- Polyhedra Pages
- Stella: Polyhedron Navigator – Software for exploring polyhedra and printing nets for their physical construction. Includes uniform polyhedra, stellations, compounds, Johnson solids, etc.
- The Uniform Polyhedra
- Virtual Reality Polyhedra – The Encyclopedia of Polyhedra
- Paper Models of Polyhedra Many links
- Paper Models of Uniform (and other) Polyhedra
- Interactive 3D polyhedra in Java
- World of Polyhedra – Comprehensive polyhedra in flash applet, showing vertices and edges (but not shaded faces)
- Polyhedra software, die-cast models, and posters
- Electronic Geometry Models – Contains a peer reviewed selection of polyhedra with unusual properties
- Symmetry, Crystals and Polyhedra
- uniform solution for uniform polyhedra by Dr. Zvi Har'El
- Java applet with the use of kaleido
- Origami Polyhedra – Models made with Modular Origami
- Polyhedra Collection – Various virtual and physical polyhedra models