Online casinos allow players to gamble over the Internet as well as in the comfort of whatever place they may be in rather than traveling to wherever their favorite establishments are situated. They are generally known as Internet casinos or virtual casinos because of this.

Much like their tangible "brick and mortar" counterparts, lottery website online casinos have ratings in the type of payback percentages and odds. A number of them even publish payout percentages on their own sites, vaunting higher payback and higher frequency than their competitors.

Payback percentage is defined as "is the overall percentage that a machine will return to the player within the long run." This parameter is generally programmed into whatever game the virtual casino may be running and is set according to the owner's specifications.