Some casinos offer Referral bonuses for those players who bring their friends to the casinos. There are two types of Referral bonuses: one for the Referee and one for the Referrer. The Referee gets a bonus when he or she registers an account at the casino and mentions the Referrer. The Referrer gets a bonus when the Referee completes all the requirements, such as making the deposit and wagering it a certain number of times. Please see the list of casinos that offer Referral bonuses here.