A slot is a position on a computer motherboard where an expansion card can be inserted. Generally, the slots are labeled as AGP, ISA, PCI, or RAM. Some computers are designed with a single slots while others have multiple slots to accommodate different types of expansion cards.
In slot machine games, a player inserts cash or, in “ticket-in, ticket-out” machines, a paper ticket with a barcode into a designated slot on the machine. The machine then activates the reels to rearrange the symbols and pays out credits based on the paytable. The symbols vary by game, but classic examples include stylized fruit, bells, and stylized lucky sevens. Most slot games have a theme, and bonus features usually align with the theme.
In the past, all slot machines used revolving mechanical reels to display and determine results. The number of possible combinations was limited by the fact that each symbol could only occupy one stop on each physical reel, and the odds of a given symbol appearing were proportional to the number of stops. This system was eventually replaced by electronic reels that weighted symbols according to their frequency on the displayed reels. This allowed manufacturers to offer jackpots with a much higher probability of being won, but still restricted the size of potential payouts. Today, many slot games have multiple paylines, allowing players to choose how many lines they wish to bet on per spin. This is known as a variable-line slot, while slot machines that always wager on all lines are called fixed-line slots.