A narrow notch, groove, or opening, as in a door or window, or the slit for a coin in a vending machine. Also: a position in a group, series, or sequence; an allotment of time or space; a berth on a ship or airplane; a spot or place in a line or column. From Middle Low German, Middle Dutch slit, from Proto-Germanic *sluta (source also of Old Norse slitr, German Schloss “bolt, bar, lock, or gate”), perhaps from PIE root *klau- (see slot). The figurative sense of “a position in an organization or hierarchy” is attested from 1942.

A slot in a computer game is the number of positions that can be filled by symbols to form a winning combination. Many slots have multiple paylines, which provide more opportunities to make a win than traditional machines with just one horizontal line of matching symbols. Usually, the number of paylines is listed in the Pay Table or information table for the slot.

The probability of a particular outcome in a slot game is calculated by dividing the total number of possible outcomes by the overall number of combinations. The house edge is calculated as the average amount that a casino will lose over a long period of time when the odds are on its side. The odds in a slot machine are calculated by using a Random Number Generator (RNG), which is independent of any previous spins. This is what makes a slot a true game of chance.