Degrees to radian converter
The word "angle" comes from the Latin word "angulus" meaning corner. The most common measure of angle is degree. Also used is the radian (rad abbreviated), which is equal to 180 / pi degrees.
After measuring the angles are classified as follows: 0 degrees angles (sides together) are called zero angles. A measure angles between 0 and 90 degrees are called acute angles. Angles 90 degrees (whose sides are perpendicular) are called straight. A measure angles between 90 and 180 degrees are called obtuse angles. The angles of 180 degrees (whose sides are in the extension one of the other) is called elongation. Angles more than 180 degrees are called reflex angles.
Also, if measured with two 90 degree angles, these are called complementary angles, and if the call is measured along 180 degrees of supplementary angles. Two common tip angles with a common side and other sides on either side of a common side are called adjacent angles.