Tells is a term used in brick-and-mortar casinos that refers to subtle signs or quirks a player or a dealer exhibit, which can be used by another observant player to their advantage.
Tells include everything from body language to the smallest facial expressions, the tone of someone’s voice or words they’re saying. Experienced poker players often try to bait other players into saying more than they should and try to recognise patterns.
For example, if someone continues to smirk or has the same body movement whenever they are dealt a good or bad hand, that’s a tell. Some of the best poker players can guess the average strength of someone’s hand before the hand even begins.
For that reason, many professional poker players wear hats or sunglasses and try to remain focused on the game and unbothered by other players’ actions in order to reveal as little information as possible to others at the table.