A narrow depression or perforation; especially, one through which a piece fits or slides. Linguistics A position in a construction (often a sentence) into which any of a number of morphemes or morpheme sequences may be fitted. The position of the word slot in a particular grammatical construction is called its slot. See also slit.
In a casino, a slot is an opening in a machine through which the gambler places wagers. Until the 1990s, slot machines were mechanical; players dropped coins into slots to activate games for each spin. In live casinos, bill validators and credit meters replaced these old slot mechanisms, and slots became less of an active component of the gambling experience. Online slots use advance deposits and credits instead of coins.
Pay lines
Video slots often have multiple “paylines” that allow you to win in a variety of patterns on a single reel. The lines can go vertically, horizontally, diagonally, or in any other pattern specified by the manufacturer. Each payline is weighted to reflect the probability that symbols appearing on it will create a winning combination.
The number of paylines varies by game and by machine. Some have up to 50 paylines, which can increase your chances of winning and unlock bonus rounds or free spins. Before playing, be sure to read the rules of each specific slot.