What is an angle?

An angle is a measure of a turn, measured in degrees or °. There are 360° in a full turn. You can find out the size of an angle using a protractor.

• An angle less than 90° is acute.
• An angle between 90° and 180° is obtuse.
• An angle greater than 180° is reflex.
• An angle of exactly 90° is a right-angle.