# Prism

A prism is a space figure with two parallel bases that are polygons of the same size and shape. All other faces of a prism are rectangles or other parallelograms. The shape of its bases gives a prism its name. For example, from left to right in the figure below are shown a square prism, a rectangular prism, and a triangular prism.

### rectangular prism

A rectangular prism is a prism that has rectangles as bases. Each of the rectangular prisms in the figures also has rectangles for its other faces. Some people call this kind of prism a right rectangular prism or cuboid. Its vertices form right angles.

Some rectangular prisms are oblique. Not all of the vertices of oblique rectangular prisms form right angles.

### Did you know?

The word "cuboid" is formed from "cube" (a noun) and "-oid" (resembling or having the properties of the noun). Look at the drawings of the rectangular prisms or cuboids. In what ways does each rectangular prism resemble a cube?

### triangular prism

A triangular prism is a prism that has triangles as bases:

See also base, cube, oblique angle.