Friction is a force that opposes the motion of objects that are in contact with each other. When two surfaces rub against each other, the force of friction slows down or stops the movement of one surface over the other.
Types of Friction
Static Friction: This type of friction occurs when two surfaces are not moving relative to each other. For example, when you try to push a heavy box and it doesn't move, static friction is at play.
Sliding Friction: Sliding friction occurs when two surfaces slide past each other. This is the type of friction you experience when you rub your hands together.