In a casino, slot is the term used for a machine that allows players to spin reels and match symbols together to win prizes. Online slots are a lot like the brick-and-mortar versions in that they come in various shapes, sizes and themes. They often come with multiple paylines and the amount of matching symbols that land on a payline will determine how much a player wins.

When playing online slot games, players can often find a pay table, which outlines how much they can win for matching certain symbols in a specific sequence. These tables are usually displayed in a tabular format and can be highlighted in different colours to make them easier to read.

During the early days of slot machines, there were only 22 symbols that could appear on the reels. This limited jackpots and the number of possible combinations. Once manufacturers incorporated microprocessors into their machines, they were able to give each symbol different weighting. This meant that winning combinations could occur more frequently than they would on a physical reel.

The pay table will also list a slot’s rules and any bonus features that are available. This is especially important for new players who may not be familiar with the game’s terminology. The rules will also explain the payback percentage and return to player percentage (RTP), which tells players how much a machine is expected to payout over time. If a slot pays out more than it should, it is considered a high volatility slot.