Principle objective of this article is to Define and Discuss on Radians. Here explain Radians in Trigonometry terms. A central angle of a circle has an angle measure of 1° if it subtends an arc that may be 1/360 of the circumference on the circle. This form of angle measure is reasonably common. Another form of angle measure that may be in use is radian evaluate. If a central point of view subtends an arc that may be equal to the radius on the circle, then this central angle has a measure of one radian.