Angle

An angle is the figure formed by two rays (or line segments) meeting at a point. The rays are the sides of the angle, while the point is its vertex. The size (or measure) of the angle is usually measured in degrees and is determined by the amount of rotation (or turn) about the vertex that would be required to move one side of the angle onto the other side. The size of the angle is often loosely referred to as the angle itself, e.g. "an angle of 60o."