Mind sports

A game of skill is a game where the outcome is determined mainly by mental or physical skill, rather than by chance. Some commonly played games of skill include: chess, poker, collectible card games, contract bridge, backgammon, and mahjong.

However, most games of skill also involve a degree of chance, due to natural aspects of the environment, a randomizing device (such as dice, playing cards or a coin flip) or guessing due to incomplete information. Some games of skill such as poker may involve bluffing and other forms of psychological warfare.

The distinction between "chance" and "skill" has legal significance in countries where chance games are treated differently from skill games. The legal distinction is often vague and varies widely from one jurisdiction to the next.

On associating Rummy, another game of skills, with gambling in 1968, Supreme Court said, "Rummy requires certain amount of skill because the fall of the cards has to be memorised and the building up of Rummy requires considerable skill in holding and discarding cards. We cannot, therefore, say that the game of Rummy is a game of entire chance. It is mainly and preponderantly a game of skill. The chance in Rummy is of the same character as the chance in a deal at a game of bridge." The decision was challenged in Supreme Court and the final verdict came in August 2015, calling Rummy a game of skills, including web portals like RummyCircle.

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Wikipedia