According to Newton's Third Law of motion, whenever two objects interact, they exert equal and opposite forces on each other.
This is often worded as 'every action has an equal and opposite reaction'. However, it is important to remember that the forces act on two different objects at the same time.
Newton's Third Law can be applied to examples of equilibrium situation.
There are contact forces between the person and the pram:
There are contact forces between the tyre and the road:
There are non-contact gravitational forces between Earth and the satellite: