Millions of people in the United States want a safe, secure way to wager on sports. That would benefit the leagues that farcically oppose it, the fans who love to watch their team lose every week and the state legislatures that are debating it.

A “sportsbook” is a company that accepts bets on a variety of sports. They determine the odds for a given bet based on complex (and secret) analytics and algorithms, take juice (their profit), and then publish those odds. Odds can differ slightly from site to site, so it’s worth shopping around to get the best price.

The most common bets are against the spread and over/under totals. A spread bet is a bet that tells you how many points the favorite team must win by to cover the point spread, while an over/under bet predicts the total number of runs, goals, or points scored in a game. A “push” is when neither team covers the spread, meaning nobody wins and all bets are refunded.

Other popular bets include parlays, a grouping of straight bets that pay out much more than their constituent parts. Hitting a “exacta” requires picking the first two finishers in exact order; a “quinella” is the same thing but with any order; and a “trifecta” is three or more winners. You can also bet on futures, which are wagers that won’t pay out until a later date, often weeks or months. These are most commonly placed on major events like the Super Bowl and NCAA Basketball National Championship.