**A 360 degree angle is called a full circle.** Angles can be measured from zero degrees all the way to 360 degrees because 360 degrees is one full rotation.

An angle that measures 180 degrees is referred to as half a circle. A quarter of a circle is called a right angle. Anything under 90 degrees is considered acute, and anything over 90 degrees is called obtuse. A protractor is a tool that is used to measure the degrees of an angle up to 180 degrees, but there are also full protractors that measure the exact angle of every line in a circle.