Online slot games can come in many shapes and sizes, from the simple three-reel classics like Starburst to five-reel megaways games with intricate graphics and engrossing themes. The variety of choices can make it hard to choose, but knowing what to look out for can help you find the perfect game for you.

Most slots work on the same principles as physical slot machines, taking in money to spin the reels and spitting out payouts if certain symbols line up on paylines. Those payouts are triggered by the random number generator (RNG) in the slot machine software, which selects a series of numbers every second until it finds one that matches up with a particular outcome on the reels. When you press ‘spin’, the RNG will generate a new number and the mathematical module in the slot machine software will use it to calculate the result.

Another factor to consider when choosing an online slot is its volatility, which is often labelled as low, medium or high. This tells you how often a slot pays out small wins and the magnitude of those wins, with high volatility slots providing little in the way of regular wins but delivering big wins more frequently.

Other features to watch out for include a wild symbol that substitutes for any other in a winning combination and multipliers that boost your wins – if you hit a x2 on a winning payline, you’ll double your win, and a cascading reels feature that replaces existing symbols with fresh ones, potentially resulting in more wins. Some slots also feature a progressive jackpot that can grow until a player hits it in a bonus round or randomly. These jackpots are usually a fraction of the overall game’s total stake, but can add up to a life-changing sum of money.