Free play slots offer players the chance to try out new games with no risk. They’re often found at casino sites and come with a variety of bonus features. Some even have a progressive jackpot that pays out over time. Some are simple pick ’em bonuses and others are more like interactive adventures where you choose from a number of options.

Online slot machines are developed by various software providers and come in a range of styles. Some have a three-reel layout with a single payline and basic symbols, while others feature five or more reels and more complex graphics. Many have different themes, including mythology (like Zeus III), history (like Kronos Unleashed) and international flare (like Rainbow Riches).

There are also a variety of bonus features that can increase your chances of winning. These can include scatters, retriggers and multipliers. Many of these can be triggered by getting specific combinations of symbols on the reels. For example, landing three scatters in a game can trigger a special free spins bonus feature that awards you with extra spins and multiplies your winnings.

Another type of bonus is the hold and spin feature, which allows you to select a regular symbol and hold it while all other symbols re-spin. Each spin of the reels that you don’t select will award you with a cash prize, which can increase if additional matching symbols appear. This is a simple, yet effective way to boost your bankroll and can be particularly useful when you’re on a winning streak.

Progressive jackpots are a common bonus feature in online slot machines. These are linked across multiple machines and the amount of each bet is added to a pool that grows over time. When a player hits the jackpot, they win the whole prize pool. These can be huge amounts and are a great incentive for people to keep playing.

Multipliers can be a key part of any slot machine, especially in free online games. They multiply your winnings by a set percentage and are commonly found in video slots with higher payout frequencies. However, these bonuses are not always available in all games, so be sure to read the paytable before you play.

Bonus rounds are a great way to spice up your gaming experience and can be as simple as picking the right combination of symbols to win. These can also lead to more lucrative prizes, such as jackpots or bonus games that allow you to play with other characters or even enter a lottery-style draw for a big prize.

A final popular feature in online slots is the use of wild symbols, which can substitute for other symbols on a payline and potentially result in bigger wins. These can come in several forms, such as expanding, stacked and sticky, so make sure to check a game’s paytable before you play. Some online slots also feature wild reels that can re-spin for more chances to make a big prize.