In a Cartesian plane, the first quadrant is for the angles with measures greater than 0 but less than 90°.
Second quadrant: greater than 90° but less than 180°
Third quadrant: greater than 180° but less than 270°
Fourth quadrant: greater than 270° but less than 360°
If we start off from the fourth quadrant (that being in clockwise direction), the object will have negative angular velocity.