A bonus code is a special code which can be used to claim a specific type of bonus. It can be used by anyone who has accessed the online casino website through a particular link or by entering the code in the designated box. Generally, a casino will provide a bonus code to those that sign up for its services, or as a promotional offer for existing players. Generally, the bonus code will offer some kind of reward, such as free spins, free credit, or discounted rates on a gambling activity.