What is a "welcome bonus"?

Since online casinos know that they face a lot of competition, they do everything in their power to make all their players happy. Generally, there is a ?welcome bonus? when you open an account for real money. Typically it looks kind of like this: you deposit a $100, and get another $100 free. This means you have $200 to play with. Bear in mind however, that you can?t cash out that bonus until you have wagered a certain amount, to prevent dishonest players from simply taking the free money. People used to do this in the past and this forced the casinos to put restrictions on the bonus. But, Hey! You still get free money to play with, and free money is still free money!