Rotational symmetry

Rotational symmetry describes a shape that looks exactly the same after being rotated by less than a full turn. The number of distinct positions that look the same is the order of rotation.

For example, a square has rotational symmetry of order 4: it matches itself after each 90° turn. The center of rotation is the point the shape turns around. A shape with no rotational symmetry only matches itself at 360°.

Rotational symmetry is one kind of symmetry; the other common kind is reflection (mirror) symmetry.