Wild symbols act like jokers and complete winning paylines. In some cases, you may earn a multiplier (2x, 3x) on any winning payline the wild helps to complete.

Some slots games award a single re-spin of the reels (for free) if you land a winning combination, or hit a wild.

This bonus is triggered by landing three or more scatters. You are taken to a 'second screen' where you have to select from mystery objects. Cash prizes, free spins, or multipliers are revealed until you hit a 'collect' symbol and return to the main base game.

An instant win, or 'click me' bonus, is awarded if you land three scatters on the reels. Simply select one of the three symbols on the reels to reveal a real cash prize.

The prize trail is a second-screen bonus triggered by hitting three or more scatters. You must then work your way along a road or trail, picking up cash, multipliers, and free spins.

Like the popular casino game, the Wheel of Fortune is often used to determine a progressive jackpot award. Land the wheel in the right place to earn the largest amounts.

By studying the paytable you can get a rough idea of how volatile (also often referred to as 'variance') a game is. The volatility is the frequency between big wins. The more volatile slots have larger jackpots but they hit less frequently than the smaller prizes.

Even in free slots for fun, you can manage your bankroll to see how good the game is long-term. If the slot has a stop-win or stop-loss limit, use it to see how frequently you win or lose.

Wilds and scatters appear in many online slots and can add serious money to a bankroll: study their payouts and multipliers (if any) to see if the slot is worth committing cash on.

With thousands of free bonus slots available online, there's no need to jump straight into real money play. You can test out hundreds of online slots first to find a game that you enjoy. Getting bored with a slot is the easiest way to go broke.

Even if you play free slots, there are casino bonuses to take advantage of. Many casinos offer free spins on the latest games, and you can keep your winnings if they meet the site's wagering requirement. Find a good slot, take advantage, and remember to have fun!

A large number of the real money slots and free slot games you'll find online are 5-reel. These play on five vertical reels, usually with three or four rows of symbols added horizontally. Winning combinations are made by lining up two or more matching symbols on a horizontal payline. Free slot machine games with free spins often feature five reels. NetEnt (top titles include Dead Or Alive, Gonzo's Quest, and Aliens) and Microgaming (top titles include Jurassic Park, Thunderstruck II, and Tomb Raider) are gaming software leaders. Experienced land-based providers, such as IGT and WMS/SG Gaming, also supply online versions of their free casino slots.

Why play 40 or 50 paylines when you can utilize the entire screen? Multi-line (or multi-way) free slots games offer up to 4,096 ways to win by having matching symbols run left-to-right and right-to-left. Multi-way slots also award prizes for hitting identical symbols on adjacent reels. The variance can be high but the potential prizes can be huge.

Many online slots have at least one bonus game. This is an extra feature that can be triggered by landing a specified number of special symbols on the reels. Bonuses include free spins ( or 'free games'), a 'pick 'em' bonus with a selection of hidden prizes, or an 'in-reel' bonus where you select symbols on the reels themselves to reveal a cash sum.

Progressive jackpots on online slots can be huge due to the vast number of players placing bets. Each time a progressive jackpot slot is played and not won, the jackpot increases. Wins are infrequent but life-changing if landed!