The activity below shows common angles in degrees and radians. If you like, you can hide one set of the measures of the angles so you can quiz yourself.
When checked, the “Move by π/12 radians” option means that when you drag the green ball to change the angle, the angle changes in increments of π/12 . This makes it easier for you to locate common angles. It is also a useful feature to find common angles stated in degrees.