Non contact forces are action at a distance forces.
two objects exert forces on each other though they are not in contact with each other.
examples are gravity, electric, magnetic , electromagnetic forces. Even nuclear force is an example of non contact forces. To illustrate an example take gravity. Our very survival on earth depends on gravity. An object that is thrown up reaches the ground because of gravity. If there was no gravity we would be floating. Electric forces are used to generate electricity