Every bonus might have its own terms, but normally bonus terms include several points. The main one is a wager. This is a number of times you need to play the bonus through to be able to withdraw your winnings. Other crucial details are a list of restricted games, maximum bonus amount, withdrawal limits, and time given for playthrough. For some bonuses, a bet amount during a playthrough can be limited or there might be other restrictions. Anyway, you will need to read the rules before accepting any deal. Violation of bonus terms might lead to annulling your bonus and winnings.