Angular Displacement

What is Angular Displacement? Is it a vector or scalar quantity? What are three conditions for Angular Displacement?

It is the angle described by a particle from one point to another, with respect to time. Since the angular displacement has both magnitude and direction, therefore it is a vector quantity.

In order to completely represent an angular displacement by a vector, it must fix the following three conditions:

1. Direction of the axis of rotation,
2. Magnitude of angular displacement, and
3. Sense of the angular displacement.