A prism is a polyhedron for which the top and bottom faces (known as the bases) are congruent polygons, and all other faces (known as the lateral faces) are rectangles. (Technically, when the sides are rectangles, the shape is known as a right prism, indicating that the lateral faces meet the sides of the base at right angles. In this lesson, when we use the term prism, we mean a right prism. But there are other types of prisms, too.)
A prism is described by the shape of its base. For instance, a rectangular prism has bases that are rectangles, and a pentagonal prism has bases that are pentagons.
Explore & Play with Prisms
Use the animation below to explore the properties of four prisms. Follow the instructions below to change the direction and speed of the prism's rotation and to highlight the numbers of faces (F), vertices (V), and edges (E) for each prism.