Fair play
Fair play is the rule that every game must be decided by the players' own thinking, which means no engine help, no advice from others during play and no tricks that distort a result.
Also called: fair-play policy
Fair play covers everything that keeps a game honest. The central rule is simple: while a game is in progress, you may not use an engine, a database or another person to choose your moves. Tournaments enforce this with arbiters, rules on phones and electronic devices, and sometimes statistical checks of games. Online, organizers use their own detection methods and publish their own policies, which differ from place to place. For a club player the practical meaning is mostly about habit. Do not look at an analysis board during a live game, do not leave a rated game to consult something, and do not accept hints from a friend. It also covers conduct such as not stalling, not making false claims and not manipulating ratings. The common mistake is thinking small help does not count. Even a single looked-up move breaks the rule. A good habit is to treat analysis as something done after the game, which is also where it helps your improvement most.
A neighboring idea is Syzygy tablebases. Syzygy tablebases are a compact set of endgame tablebases created by Ronald de Man that cover endgames up to seven pieces and are widely used by modern chess engines.
An engine can tell you what "Fair play" means for a position, but not which mistakes you keep making; a first lesson with George Li reviews your games and finds those.
Related terms
A chess engine is a computer program that searches positions and evaluates moves, usually playing and analyzing far stronger than any human, and it is used for analysis, preparation and play against a machine.
Engine analysis is the use of a chess program to search a position and report which moves are strongest, along with a numeric evaluation and the lines it expects both sides to follow.
The arbiter is the official who sees that the Laws of Chess and the rules of the event are followed, rules on disputes and claims, and can penalize rule breaches during a tournament.
The rules of chess are the Laws of Chess, the document FIDE publishes that sets out how pieces move, how a game ends, how clocks and records work, and how arbiters handle problems.
An online rating is the number a website or app computes from games played on that platform; it belongs to that site's player pool and is separate from FIDE and national over-the-board ratings.
Guides that go further
What to decide first, the questions to ask, what a first lesson should show and the red flags to avoid.
How much does chess coaching cost?
Published rates for private, group and subscription chess coaching, with the source and the date of each.
A game review, a read on your level and a written study plan from George Li.
Want to spot this in your own games?
A first lesson starts with your games: George reviews them and builds a study plan around what he finds.