Earthing
"Earthing" a charged object means removing charges from the object.
Put some negative charge on a metal ball using the method of induction. Then touch the ball with your hand.
The moment you touch the ball, all the charges on the ball will be removed. Electrons from the ball will flow into your body.
Our hand is slightly conducting. Because our body is a lot bigger than the metal ball, we also have a lot more electrons that can be moved around. These mobile electrons are like a reservoir. (You can take some or add some water to a reservoir without changing the water level, because there is so much water.)
So because there is an excess of electrons on the metal ball, these can all flow into your body when you touch it. This is one way of removing charges.
Note that this would not work if we have a plastic ball. A plastic ball is an insulator, so electrons on the ball cannot just flow out. (One way to earth a charged insulator is to put it over a candle, and play the flame very quickly over all parts of the surface.)