Official betting is a legal way to place a wager on sports. It involves placing a bet on an outcome that you believe will happen, and getting paid if it does. There are many types of official betting, including money lines, spreads and parlays.

The odds of an event change in real time based on the share of total exchange each possible outcome has received from bettors. This is similar to parimutuel wagering in horse racing and dog racing.

Players can also use the official stream of a game to place their bets. However, it is important to note that bookmakers are a few seconds ahead of you when using these streams, which can make an impact on the odds of your bet.

There are some rules that apply to official betting, such as the rule against bribery or inside information. Some people may have been permanently banned from the sport they play for violating these rules, while others have only lost their license.

In 1919, eight members of the Chicago White Sox were banned from professional baseball for fixing the World Series against the Cincinnati Reds with help from a bookmaker named Joseph Sullivan. In addition, anyone involved with a national baseball team cannot bet on an MLB game.

There are also certain rules for betting on college football. Most states have ruled that wagering on in-state college teams is illegal through mobile apps, but some allow retail books to offer action.