A mirror whose polished, reflecting surface is a part of a hollow sphere of glass is called a spherical mirror.

A spherical mirror whose outer surface is reflecting surface is called a convex mirror.

A spherical mirror whose inner surface is reflecting surface is called a convex mirror.

A concave mirror is also called converging mirror because a parallel beam of light incident on it, converges to a point after reflection.

Convex mirror is also called a diverging mirror because a parallel beam of light incident on it, appears to be diverging from a point after reflection.