A

David

Darling

rotation

In physics, rotation is the turning or spinning of a body, such as a planet, star, or galaxy, about an axis running through it. See also rotational period.

 

In mathematics, rotation is a transformation in which a figure turns through a specific angle about a fixed point, called the center of rotation. The center of rotation may be inside or outside the figure that is being transformed. If the figure is turned anticlockwise, the rotation is considered positive, while a negative rotation turns the figure clockwise.