This document discusses different types of forces. It defines force as a push or pull on an object that can be caused by the interaction between two objects. There are two main types of forces - contact forces that occur when objects touch, and non-contact forces that act over a distance like magnetic, electrostatic, and gravitational forces. Contact forces include muscular force and friction. Non-contact forces are illustrated by examples of magnetic, electrostatic, and gravitational interactions. The document also discusses how multiple forces combine into a net force, and how forces can affect an object by changing its motion, speed, direction, or shape.