In Forbidden Island, you play as a team. Your goal is to collect all the four items. The water, the fire, the land, and the sky. If someone from your team has 4 of one card, then they can go to one of the pictures of the item and collect it. When you are done, you leave via fools landing.
A good strategy is to shore up all of the locations that you need to play the game. These are the places for the items and fools landing. If fools landing floods, you lose. You also should shore up any cards that help you get to the important places. If both of the places for each item flood and you haven't collected the item, you lose.
This game is one in a series with forbidden desert and forbidden sky afterward. Up to 4 players. I think.