Describe the difference between a prism and a pyramid.

A prism and a pyramid are both three-dimensional shapes, but they have some key differences:

1. Base Shape: A prism has two bases that are parallel and congruent (exactly the same). These bases can be any polygon (a shape with at least three straight sides and angles), such as a triangle, square, rectangle, etc. On the other hand, a pyramid has one base, which can also be any polygon.

2. Faces: The faces of a prism are parallelograms (four-sided shapes with opposite sides that are equal and parallel). A pyramid, however, has triangular faces that meet at a common point called the apex.

3. Volume: The volume of a prism is calculated by multiplying the area of the base by the height of the prism. The volume of a pyramid is calculated by multiplying the area of the base by the height of the pyramid, and then dividing by 3.

4. Examples: Examples of prisms include a rectangular box, a cylinder, etc. Examples of pyramids include the Egyptian pyramids, a cone, etc.

In summary, while both prisms and pyramids are three-dimensional shapes, they differ in the number and shape of their bases, the shape of their faces, and the way their volumes are calculated.