Nothing bonds people faster than shared embarrassment, which is what makes Truth or Dare such a classic party game. To play Truth or Dare, you'll need at least two players -- more is better -- and a relaxed social environment.
Choose a player to begin. This player picks another player and asks him "truth or dare?" If the chosen player picks "truth," the first player than asks him a question which he has to answer truthfully. If he chooses "dare," the first player chooses a task he has to perform. The first player can choose whatever question or challenge she likes, but it's normal to choose something that will make the player look silly or awkward. Questions such as "what's the dumbest thing you've ever said in public" or "tell us about the worst date you've ever been on" are typical, just make sure not to get too personal: Hurt feelings can ruin the game quickly. Dares can include physical stunts or impromptu performances, but make sure to avoid anything illegal or a stunt that could cause physical harm.
Once the first chosen player completes his question or dare, play passes to him. He now chooses another player and repeats the truth-or-dare process. As with most party games, there is no way to win Truth or Dare; play continues until everyone gets bored or something else comes along.
Although Truth or Dare doesn't have many rules to change, there are a few common variations. One variant rule encourages variety by forbidding a player from choosing either "truth" or "dare" three times in a row. Another common house rule is to require each player to play once before the first player takes another turn.