This is a bonus given from the bookmaker as a kind of reward to the new customer for joining his site. As the player becomes regular with his bets and becomes familiar with this online betting game, more such offers are passed on by the site in various forms. Some of the bigger names in the sports betting field are regular with such free bets. Online betting has become very popular and one feature that has made it so is the free bet offer provided by many bookmakers to new customers.