**Bases:**A prism has two bases, which are congruent polygons lying in parallel planes.**Lateral edges:**The lines formed by connecting the corresponding vertices, which form a sequence of parallel segments.**Lateral faces:**The parallelograms formed by the lateral edges.

A prism is named by the polygon that forms its base, as follows:

**Altitude:**A segment perpendicular to the planes of the bases with an endpoint in each plane.**Oblique prism:**A prism whose lateral edges are not perpendicular to the base.**Right prism:**A prism whose lateral edges are perpendicular to the bases. In a right prism, a lateral edge is also an altitude.