Online casinos allow players to gamble through the Internet and in the comfort of what ever place they may be in rather than traveling to wherever their favorite establishments are located. They may be also known as Internet casinos or virtual casinos because of this.

Just like their tangible "brick and mortar" counterparts, online casinos have ratings in the form of payback percentages and odds. Many of them even publish payout percentages on their 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 in the long haul." This parameter will be programmed into what ever game the virtual casino could be running and is set as outlined by the owner's specifications.

Due to its very nature of being virtual and intangible, online casinos have trust problems with prospective and even regular clients. In light of this many casino owners have purchased and/or leased proprietary software made by reputable software entities like CryptoLogic Inc, Realtime Gaming, Microgaming, and Playtech. They then peg their online casino's trustworthiness with the programming companies' reputations as well as the stability of their random number generators.

Online casinos are classified into three types according to how players interact with each other. They are:

Web-based online casinos - these types of virtual casinos don't require downloading files; they readily play by way of a wide range of Internet browsers. A lot of them require Flash or Java for a player to participate in games however. The advantage of this kind of casino is the fact that sound clips and graphics needed for the game is streamed directly to the client over the Net. This dispenses the need to download relatively huge files.

Download-based online casinos - Taking part in this type of casino involves downloading a client installer needed for players to gain access to the virtual site. The benefit from this sort of casino is the fact that it generally runs much faster than Web-based ones. The disadvantage is that interested players need to download the client and the risk of installing malware from shady parties can be very much real.

Live-based casinos - Within this kind of casino, players can hear, see, and connect to other players. The internet is simply relatively an unobtrusive medium of communication as players participate in a real world environment.

Online casinos may offer anyone or all of the following gambling pastimes: online poker, roulette, blackjack, baccarat, craps and online slot gacor games.