A slot is a special place for something that can fit into it. The word is a compound of two other words: slot, meaning “place for a thing,” and slit, meaning “a narrow piece of cloth or leather” (as in a sleeve). The original sense developed from the fact that electromechanical slots had tilt switches that would make or break a circuit, indicating a malfunction. Modern machines, however, usually have no such mechanical faults. Rather, they may be “tilted” in some other way (door switch in the wrong state, reel motor failure, out of paper, etc.).
A slot can also refer to the space within a physical machine for accepting cash or, in “ticket-in, ticket-out” machines, a paper ticket with a barcode. The machine then activates one or more reels to rearrange symbols, and pays out credits according to the paytable. Symbols vary depending on the theme, but classic symbols include fruits, bells, and stylized lucky sevens.
Many video slot games have multiple paylines, increasing a player’s chances of winning by allowing more combinations on each spin. Some even have a popular mechanic called Megaways, where each reel has more than three rows and columns to allow for a large number of possible positions for symbols.