A Base!
The only two parallel faces on a prism are the ends.
They are the lateral faces.
A rectangular prism with 6 congruent faces is called a cube.
A Base. * * * * * What? Every prism, by definition, has two congruent faces which may be called the bases of the prism.
It could be called a square prism but a more common name would be a cuboid.
A prism has 2 congruent parallel faces called bases. The other faces, most often rectangles, are called lateral faces. The prism is named by the shape of its base.
It is a Triangular Prism.
A pentagonal prism has 7 faces.
Faces?
A rectangular prism has: 6 faces 8 vertices (points) 12 edges
The flat surfaces of all polyhedra are called faces and a rectangular prism is simply one kind of polyhedron.
Faces