Gambling was a game of chance and form of recreation that involves betting with currency such as tokens (or chips), money, or latinum, on the outcome of betting games or betting pools. Casinos are popular venues for gambling.
In 2371, Dr. Bashir ordered Major Kira to relax during a particularly stressful period. With the assistance of Quark, Bashir prescribed several means of relaxation, which included a small stack of gambling tokens to use for gambling. (DS9: "Defiant")
Although the odds are typically in the favor of the "house", a skillful player may go home a winner. Other times, a not-so-skilled played may accrue quite a debt.
Someone who is often quite skilled at a game but feigns their true abilities are often called "hustlers". Notable hustlers include Jake Sisko at dom-jot and Kathryn Janeway at pool. (DS9: "The Abandoned"; VOY: "The Cloud")
Interstellar Legal Status
The Bajoran Provisional Government has legalized gambling within Bajoran territory, which includes Deep Space 9 and its bar Quark's. Nonetheless, Bajoran law has restrictions against cruelty to animals, and thus Quark's repeated attempts to stage gambling on live Vole fights are still considered illegal on DS9. (DS9: "Through the Looking Glass", DS9: "Destiny")
When Lt Tom Paris created the short-lived Paris Radiogenic Sweepstakes aboard the USS Voyager, a lottery whose winner was the one to correctly guess the radiogenic particle count the next day, Commander Chakotay shut it down. (VOY: "Meld")
Gambling is legal in the Cardassian Union, as Quark was operating casino games in his bar during the Cardassian Occupation of Bajor. Gambling is also shown to be legal in the Ferengi Alliance and regulated by the Ferengi Gaming Commission. The Ferengi also operate casino ships.