I thought I understood what a force is. Recently I'm reading up on it more thoroughly and found several 'interpretations'. Definition: A force is a push or a pull; produces or tends to produce motion, and stops or tends to stop motion. Question: What type of forces are there? Answer 1: Two - push and pull Answer 2: Two - contact force (eg. friction) and non-contact force (eg. gravitational force) Answer 3: Two - contact force and force field (??) Answer 4: There are many types of forces, such as weight, friction, tension, resistance. Those are some answers I found. Does the phrasing of the question matter? "What type of forces are there?" vs "What are some examples of forces?" This may be a fundamental concept so I hope to get a clear picture of what it is to help me in my own tutoring. Thanks much!!