The 2007 World Series of Poker was the 38th annual World Series of Poker (WSOP). Held in Las Vegas, Nevada at the Rio All Suite Hotel and Casino, the series featured 55 poker championships in several variants. As a WSOP custom since 1976, each of the event winners receive a championship bracelet in addition to that event's prize money. The series culminates with the $10,000 No-Limit hold'em "Main Event", which has attracted thousands of entrants since 2004. The winner of the WSOP Main Event, who wins a multimillion-dollar prize, is considered to be the World Champion of Poker.
Most of the tournaments played at the WSOP are variants of Texas hold'em, a game where each player may use a combination of the five community cards and two hole cards to make the best hand. Another poker variant with community cards is Omaha, in which each player is dealt four hole cards and must use two of them in conjunction with three of the five community cards to make the best possible five-card hand. In contrast to games with community cards, some variants, such as stud or draw, deal each player separate hands with no common cards. Seven-card stud deals each player two hole cards, followed by four face-up cards one at a time, and then another hidden card, with betting after each round. Other games played at the 2007 tournament included Razz, H.O.R.S.E., and Deuce-to-Seven. Prior to 2000, seven-card stud was the most common game in U.S. casinos, but today hold'em has almost totally eclipsed the once popular game.
Within each of these poker variants, a myriad of options exist. For example, depending on the betting structure, a tournament might be described as no-limit, limit, or pot-limit. Games may include other variations on the rules governing the execution of the specific game such as shootout, eight or better, or heads up.