The game of slots uses symbols in a paytable to determine how much the player can win. These symbols can be multiple of one type and may appear on the same pay line or they may represent many different symbols. The pay table is usually displayed on the machine’s face, above or below the spinning wheels. In some cases, the pay table is also available in the help menu.

Slot machines are legal in most states. Some states have restrictions, though. For example, Nevada does not allow private ownership of these machines. In New Jersey, slot machines are allowed only in hotel casinos. In Louisiana and Missouri, slot machines are allowed only on riverboats. After Hurricane Katrina, Mississippi removed this restriction and allowed casinos to open on its Gulf Coast. In Delaware, slot machines are only allowed at three horse tracks and are regulated by the state lottery commission.

In the 1960s, Bally developed the first fully electromechanical slot machine. The basic electromechanical construction was already visible in the High Hand draw-poker machine in the 1940s. Another machine by Bally, Money Honey, had a bottomless hopper and automatic payouts of up to 500 coins. This game changed the face of the slot machine industry, and the side lever became a relic of the past.

Slot machines have several components that help determine the payout percentage. The payout percentage is set at the factory when the slot machine’s software is written. In some cases, the payout percentage can be changed, but it involves swapping the software. The software is generally stored on an EPROM, but it can also be stored on CD-ROM or DVD. Changing the payout percentage is time-consuming. Furthermore, EPROMs contain a tamper-evident seal and can only be altered in the presence of Gaming Control Board officials.