Point moves along the unit circle (circle with radius ). The corresponding angle of rotation is positive when you move counterclockwise, negative if when you move clockwise. It can have any value. The height of with respect to the horizontal axis is .
For a more suitable graph we rather express the angle of rotation in radians.
The angle then corresponds to the length of the arc on the unit circle (the blue part of the circle).
correponds to radians.
This standard sine graph is periodical with period .
Look at the applet: Sine graph