Best move
The best move is the move an engine rates highest in a given position after searching, usually shown first in its list of candidate lines and marked with the strongest evaluation.
Also called: engine top choice
When analysis software labels a move as best, it means that after its search, no other move scored higher. That is useful, but it is narrower than it sounds. Several moves can be nearly equal, and the engine may rank them in an order that depends on search depth, so a move marked second may be just as good in practice. Sometimes the best move is also hard for a person to play, because it needs precise follow-up that a human will not remember. A club player meets this label in game review, where playing the best move is credited and playing something else is compared against it. The common mistake is feeling that every non-best move was an error. Most positions have more than one good move, and choosing a sound, understandable one is often the better practical decision. A good habit is to look at the top few moves, not just the first, and ask what idea each one carries. If your move scored close to the best, note the idea you used and move on.
A neighboring idea is Brilliant move. A brilliant move is a label some analysis tools give to a strong, hard-to-find move, often a sacrifice, that the engine confirms keeps or improves the position despite looking risky.
Compare it with Engine analysis. 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.
Also worth reading is Principal variation. The principal variation is the line of best play for both sides that an engine has found, shown as a sequence of moves and tied to the evaluation it reports.
Computer terms such as "Best move" are most useful next to a coach who reads your games with you, which is how a first lesson with George Li works.
Related terms
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.
Candidate moves are the small set of plausible moves you shortlist in a position before analyzing any of them in depth, so that your thinking is organized and no strong option is overlooked.
An inaccuracy is the mildest error label in game review, given to a move that is playable but gives up a small amount of advantage compared with the engine's better alternative.
An evaluation is a numerical judgment of who stands better in a position, usually given in pawns from White’s point of view, where positive favors White and negative favors Black.
The principal variation is the line of best play for both sides that an engine has found, shown as a sequence of moves and tied to the evaluation it reports.
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.