Forces that are equal in size but opposite in direction are called balanced forces. Balanced forces do not cause a change in motion. When balanced forces act on an object at rest, the object will not move. For example- If you push against a wall, the wall pushes back with an equal but opposite force. Neither you nor the wall will move.

Forces that cause a change in the motion of an object are unbalanced forces. Unbalanced forces are not equal and opposite. For example- Suppose that one of the teams in tug of war pulls harder than the other team. The forces would no longer be equal. One team would be able to pull the other team in the direction of the larger force.