A sportsbook is a gambling establishment that accepts wagers on sporting events and pays out winning bettors. In the past, you had to visit a sportsbook in person to place your bet, but today you can do it from any computer or mobile device through an online betting site. Online sportsbooks are typically less expensive to run than brick-and-mortar facilities, and they allow bettors to place bets with a variety of methods.
The betting market for a football game begins to take shape almost two weeks before kickoff. Each Tuesday, a handful of sportsbooks post what are known as look ahead lines for the coming week’s games. These initial odds are based on the opinions of a handful of employees, and they don’t go much deeper than a general assessment of each team’s strengths and weaknesses.
As the game day approaches, sportsbooks will tinker with these initial numbers. They’ll juggle the point spreads and moneyline odds between teams to attract action on both sides of the board. They’ll also adjust for factors like home field advantage, which can have a profound impact on some teams’ abilities to cover spreads and win moneyline bets.
Ultimately, sportsbooks make money by collecting a small commission on every losing bet. This is called the vig, or juice, and it’s a standard 10% for most sportsbooks. This money is used to pay bettors who won their bets, and it also helps keep the house edge low enough that savvy bettors can earn long-term profits from their picks.