Deposit Bonuses: The most common variety of online casino bonus is the deposit bonus or match bonus. It is given away as a percentage of players' deposit amounts. For example, a 100% match or deposit bonus of up to $100 means that the deposit amounts of a player will be doubled to a maximum of $100.
In short, it means that the casino will match your deposit by a certain percentage and up to a certain amount. For example, you can generally find a 100% matching deposit bonus, which could be worth up to $/ /50.00, $/ /100.00, $/ /500.00, or more (or equivalent currency value).