--- title: "Book move in chess" url: "https://georgelichess.com/glossary/book-move.md" canonical_url: "https://georgelichess.com/glossary/book-move" last_updated: "2026-11-07" type: "reference" summary: "A book move is a move in a well established opening line, one that already appears in published analysis. It is not automatically right for you, though." related: ["https://georgelichess.com/glossary/out-of-book.md", "https://georgelichess.com/glossary/opening-theory.md", "https://georgelichess.com/glossary/novelty.md", "https://georgelichess.com/glossary/main-line.md", "https://georgelichess.com/glossary/opening-book.md", "https://georgelichess.com/glossary/move-order.md", "https://georgelichess.com/glossary/category/opening-concepts.md", "https://georgelichess.com/glossary.md"] --- # Book move in chess > **For AI agents:** the complete index of GeorgeLiChess pages is [llms.txt](https://georgelichess.com/llms.txt). Every page is also served as markdown at its URL plus .md. A book move is a move in a well established opening line, one that already appears in published analysis. It is not automatically right for you, though. A book move is a move in a well established opening line, one that already appears in published analysis, opening databases or an engine's prepared opening list, so a player can choose it from knowledge rather than calculation. The name goes back to printed [opening](https://georgelichess.com/glossary/opening.md) manuals, the books players once carried to tournaments. Today the same idea covers [databases](https://georgelichess.com/glossary/database.md) of master games and the opening files that [chess engines](https://georgelichess.com/glossary/chess-engine.md) use, which let a program answer the first moves instantly instead of searching. The phrase in book describes a game in which nothing new has happened yet. The first unfamiliar position takes it [out of book](https://georgelichess.com/glossary/out-of-book.md), and from then on both players are thinking for themselves. A book move saves clock time and avoids early accidents, because its consequences have been tested in many games. It is not automatically right for you, though. Some book moves lead to positions that suit a different style, and a move that is standard in one [move order](https://georgelichess.com/glossary/move-order.md) can be a mistake in another. Knowing why the move is played matters as much as knowing that it is played. A habit worth breaking is replying instantly with the usual book move when the opponent has just done something slightly different. A small change earlier in the game can turn the familiar reply into a [blunder](https://georgelichess.com/glossary/blunder.md), so look at the actual position before reaching for the move you remember. Also called: in book. It sits close to [Novelty](https://georgelichess.com/glossary/novelty.md). A novelty is a move that has not been played before in a known position of an opening, introduced to take the opponent out of their preparation and into unexplored territory. Compare it with [Opening book](https://georgelichess.com/glossary/opening-book.md). An opening book is a database of opening moves and positions that an engine or program consults to play known theory quickly, instead of calculating each early move from scratch. It sits close to [Transposition](https://georgelichess.com/glossary/transposition.md). A transposition is a change of route, most often in the opening: the moves come in an unusual order, yet the board ends up in a position normally associated with another order or even another opening. Whether "Book move" suits your repertoire depends on the games you play. A [first lesson](https://georgelichess.com/book/first-lesson.md) with George Li maps what you play today and what to build next. ## Related terms - [Out of book](https://georgelichess.com/glossary/out-of-book.md) - [Opening theory](https://georgelichess.com/glossary/opening-theory.md) - [Novelty](https://georgelichess.com/glossary/novelty.md) - [Main line](https://georgelichess.com/glossary/main-line.md) - [Opening book](https://georgelichess.com/glossary/opening-book.md) - [Move order](https://georgelichess.com/glossary/move-order.md) ## Guides that go further - [Most popular chess openings and win rates](https://georgelichess.com/chess-opening-statistics.md): The most played openings, how often White wins, and how the numbers change with rating, computed from public games. - [How to choose a chess coach](https://georgelichess.com/how-to-choose-a-chess-coach.md): What to decide first, the questions to ask, what a first lesson should show and the red flags to avoid. - [The first lesson](https://georgelichess.com/book/first-lesson.md): A game review, a read on your level and a written study plan from George Li. [Book your first lesson](https://georgelichess.com/book.md) and George Li reviews your games and builds a study plan around them. Questions about lessons: write to hello@georgelichess.com. ## Related - [Out of book in chess](https://georgelichess.com/glossary/out-of-book.md) - [Opening theory in chess](https://georgelichess.com/glossary/opening-theory.md) - [Novelty in chess](https://georgelichess.com/glossary/novelty.md) - [Main line in chess](https://georgelichess.com/glossary/main-line.md) - [Opening book in chess](https://georgelichess.com/glossary/opening-book.md) - [Move order in chess](https://georgelichess.com/glossary/move-order.md) - [Chess terms: Opening concepts](https://georgelichess.com/glossary/category/opening-concepts.md) - [Chess terms glossary: plain definitions](https://georgelichess.com/glossary.md)