A prism is a 3D shape which has a constant cross section - both ends of the solid are the same shape and anywhere you cut parallel to these ends will give you the same shape. For example, in the prism ...

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Some examples of solids that incorporate 2D shapes are mentioned in this video by Sanchit — for example ...