A sportsbook is a place—either a physical building or an online entity—where people make wagers on sporting events. While most bets are placed on professional sports, collegiate events are also popular. A sportsbook can be legal or illegal. Some examples of legal sportsbooks are DraftKings and Bovada. However, some states don’t allow their residents to place bets on those sites.
Sportsbooks make money by taking bets on the chances that an event will occur, which are then priced based on their probability of happening. This allows punters to place bets on sides they believe will win with the sportsbook essentially taking the other side of the bet. This gives the sportsbook a profit, which is called “vigorish” in the industry.
In addition to moving handicaps in against-the-spread bets, sportsbooks will often move odds in money line and over/under bets. For example, if a team’s quarterback’s total for passing yards opens at 249.5 and the sportsbook receives lots of action on the over, they can simultaneously lower the odds (say from -110 to -125) and raise the total (say to 252.5) to induce more action on the under. Sportsbooks also move betting lines on futures bets, which are based on future events and typically have a long-term payout horizon measured in weeks or months.
The legality of sportsbooks varies from state to state, and most have rules that limit the types of wagers accepted. For instance, Nevada’s sportsbooks only accept bets on professional and collegiate events. In 1992, the Professional and Amateur Sports Protection Act limited sportsbooks to Nevada, Oregon, Montana, and Delaware, but that law was ruled unconstitutional on May 14, 2018, opening the door for sportsbooks in nearly 40 states.
