"Radians" are unit of angular measure used in mathematics. It is a measure based on the "Radius" of the circle (Radius is the straight line from the center of the circle to the circumference of a circle). Radian is the angle made when we take the radius and wrap it around the circle. (It is the plane angle subtended by a circular arc as the length of the arc divided by the radius of the arc.) The radian is represented by the symbol rad.
A radian is a unit of measurement that measures the central angle of a circle. A central angle measuring one radian intercepts or forms an arc whose length is equal to the radius of the circle.
