Friction is both a friend and a enemy.it helps in following ways:
1)it helps in gripping.
2)it helps us to walk.if there was no friction we would never stop once we set into motion.
3)it helps us to write on paper or any other thing. friction is a foe for following reasons:
1)it is responsible for the wear and tear of machines.
2)it reduces the speed of a moving object.
3)it is responsible for the wear of soles of shoes. hence it is a necessary evil.