Supercards are just like regular Bingo Cards, except that every Supercard has a Collection Item on it that you can win if you get Bingo on that card. Simply check the checkbox under the Play button to play with Supercards.
*Cost varies per room.
Supercards are not required to play Bingo. If you don't want to use them, just make sure the Supercards box is unchecked before you click the PLAY button.