Official betting is wagering that takes place with legal sportsbooks in states where gambling is permitted. It’s a form of parimutuel wagering, which involves betting odds that change in real time based on how much money each of the possible outcomes has received – and how many people have placed bets on them.

In addition to the standard money line, some games have Over/Under totals. These wagers can be on the number of runs scored in a game, or on specific categories such as first to X or total bases (a single = 1, double = 2, triple=3 and home run=4). In the case of MLB baseball, games must be played for 9 innings (8.5 if the home team is ahead) for Over/Under wagers to have action.

NBA players, coaches and other league personnel are banned from placing bets on the NBA or any of its teams or related properties. They may gamble on non-NBA events with legal sportsbooks, but they cannot bet within their own team’s facilities or while traveling with the team. They must also sign a statement acknowledging the league’s rules governing gambling.

Pennsylvania was among the first states to act after the Supreme Court’s PASPA ruling, and its retail and online sportsbooks launched in November 2018. SugarHouse became the first brick-and-mortar site to open in the state, followed by DraftKings, BetRivers and FanDuel. New Hampshire was the next to approve sports betting, with both retail and online books opening in December 2019. And Arizona legalized sports betting in April 2021, following months of maneuvering in the state Legislature and public statements of support from Gov. Ducey.