A sportsbook is a place, online or in a brick-and-mortar building, where people can bet on the outcome of a sporting event. The word sportsbook comes from the act of placing a bet, which is known as laying a bet. The goal of a sportsbook is to generate profit by accepting winning bets while simultaneously collecting funds from losing bettors in the form of a commission known as the vigorish. The amount of money collected by the bookie on bets is determined by the number of lost bets and betting rules, as well as the expected volume of winning bets.
Sportsbooks can accept a variety of bets, but the most common type of wager is the straight bet, which is placed on a single outcome. For example, if you believe that the Toronto Raptors will win against the Boston Celtics in an NBA game, you would place a straight bet on the home team. The same applies to a UFC match, where you might bet on a specific fighter such as Francis Ngannou.
To make a profit, sportsbooks set a spread (or point total) that they believe is a fair estimate of the median outcome. The conventional payout structure awards the bettor with a unit profit of phh when m > s, and 0 otherwise. Typically, s is written as +3 to denote the fact that a sportsbook is proposing a positive value for m. The required sportsbook error to permit positive expected profit is therefore 2.4 percentiles, with the upper bound bounded by the lower bound for the variance in the median outcome and the lower bound on the excess error rate.