Definition:Degree of Arc/Historical Note

Historical Note on Degree (Angular Measure)
The division of the circle into $360$ degrees originates from the Babylonians, who used a sexagesimal (base 60) number system for the purposes of mathematics and astronomy.

Degrees are usually the first way of measuring angles taught to mathematics students, usually at grade school.

Conveniently, the most commonly used angles in geometry (e.g. $30^\circ, 45^\circ, 60^\circ$) are all whole numbers when measured in degrees.