Discarding is compulsory in Rummy. It is when you place a card from your hand on to the discarded pile. Each player must end their turn by discarding one card from his hand face up on the discard pile.
If the stock runs out, the next player can draw from the discard pile or to turn it over to create a new stock. The discard pile will not be shuffled. From the new stock, the top card is drawn to form the new discard pile. Players can call “rummy” if a point is discarded into the discard pile.