Glossary
Sportsbook
A sportsbook is the company or venue that sets odds, accepts bets, and pays out winners. Also called a book, it makes money from a margin called the vig priced into its odds rather than from any single result. Its goal is balanced action, not beating you on one bet.
A sportsbook is the counterparty to your bet. It publishes the odds, takes the action, and settles the results. You may hear it called a book or a bookmaker, and today it is most often an app rather than a physical counter.
The important thing to understand is how it earns. A sportsbook is not trying to out-guess you on a single game. It prices every market with a built-in margin, the vig, and aims to attract roughly balanced money on both sides. When the money is balanced, it collects that margin no matter who wins.
That design shapes everything you see. Lines move to steer the money toward balance. Prices tighten on heavily bet markets. Knowing that the book profits from volume and margin, not from your individual loss, is the first step to reading its behavior clearly. The guide on how sportsbooks make money goes deeper.
Related