These collisions are: "a Vehicle Collision, a Human Collision, Internal Collision." A vehicle collision is a collision that involves two or more vehicles and is when the vehicles collide against each other creating a unbalanced force since how the force comes from opposite directions. A human collision would involve a vehicle and a human which would also be a unbalanced force but the human wouldn't have much affect of it's speed. A internal collision is when something happens inside the vehicle which decreases, or increases the vehicles speed.
Hope this helps!