* An object changes its direction of motion. This is the most straightforward case. If a car turns a corner, its velocity changes direction, even if its speed remains constant.

* An object experiences a change in acceleration that causes its velocity to change direction. Imagine a ball thrown straight up in the air. Its velocity is initially upwards, but as gravity acts on it, its velocity decreases until it reaches zero at the highest point. Then, gravity continues to act, causing its velocity to change direction and point downwards.

Important Note: It's crucial to understand that velocity is a vector quantity, meaning it has both magnitude (speed) and direction. So, even if the speed of an object remains constant, a change in direction will still result in a change in velocity.