The GameCube Memory Card was used for storing saved games. If you did not have a memory card for the GameCube, you could not save any games.
How The Memory Card Worked Edit
You can buy a memory card for the GameCube for under $20 right now (Maybe more earlier in the GameCube's life span). All you have to do to setup a Memory Card is,
- Insert the Memory Card into the GameCube Memory Card Slot A, or B.
- Turn ON the GameCube (Make sure the GameCube is OFF).
- To check if you did it right, you can go into the Settings/Storage setting of the GameCube, and you should see the Memory Card.
- Boot up a game, and you are ready to save a game!