Social casinos (sometimes also called sweepstakes or sweeps casinos operate on a free to play basis, which means the games are entirely free to play, and there is no deposit required. This is different from a real money casino where you are (usually) required to deposit real cash into a casino account before you can play any games. Social casinos use free coin bonuses and other welcome offers, to reward a player for signing up, and these are provided without a deposit being required, so there are also no deposit bonuses.