Online slots have become the biggest draw in online gambling, thanks to big-money movie licenses and humungous jackpots. Drawing their inspiration from physical slots machines, a longstanding fixture of pubs and casinos, online video slots combine the simple mechanics of old-school fruit machines with flashy graphics and innovative features.
Although online slots are simple games dictated by luck, they can easily overwhelm the new player with jargon and “special features”. But however complicated a particular game might seem, they usually follow a fairly similar structure.
Almost all of the meaningful decisions you’ll have to make when playing online slots will be decided before the game even begins. Depending on the particular slot you’re playing, you’ll have several decisions to make to determine how much money you bet on each spin of the wheels.
Most slots games follow the same basic pattern, with a number of symbols spread across three to five reels. While the design and format varies broadly, think of these as the digital version of fruit symbols on a fruit machine. While slots are fairly simple, there are a few particular features of online slots you should get acquainted with.
Paylines are winning combinations of matching symbols, mapped out across the reels in a number of directions. These are the patterns of matching symbols players have to line up to win. There are usually anywhere from 9 to 1,024 paylines active on a given slots game, and players often have the opportunity to decide how many lines to play at each time (with more lines equivalent to more multiples of your original stake).
Some games remove this choice, with all lines playable by default, while others do away with paylines entirely to reward clusters of adjacent matching symbols, wherever they are found on the reels. The specifics depend on the particular game you are playing, and the rules and layout of that game. Paylines usually have an equivalent value, with the size of the prize determined by the symbols themselves, with some combinations worth more than others.
Wild symbols (Wilds)
Wilds are additional symbols on the reels which act as a wildcard. In some games, a combination of wilds will pay out a wilds bonus, or introduce a multiplier that could double or triple the potential prize. Where a wild symbol falls on a payline, it will substitute for any symbol you are missing, to complete the payline and award you with a payout. Some games even introduce features like Sticky Wilds and Expanding Wilds, which give players extra opportunities to take down a big prize.
Scatter symbols (Scatters) are another type of symbol commonly found on slots reels, responsible for triggering bonus games. The usual format is that you need to land three or more scatter symbols on a given spin to trigger the bonus games, and there may be several different types of scatters in play. You can find all the information about wilds and scatters on the game’s paytable, which is always available from the game’s main menu.
Bonus games are unique to online slots, where it’s so much easier for software designers to introduce additional features, compared to physical slot machines.
Most commonly, you’ll find a free spins bonus, where players automatically pick up a number of free spins, potentially with additional multipliers thrown in. You may have to win free spins in a bonus game, or compete to determine the size of your multiplier – that’s all part of the fun. But usually if you land the required number of scatters, you’ll trigger some variation of a free spins bonus, which means your next spins will be risk-free until your free spins have been exhausted.
Some games allow you to retrigger free spin bonuses during your free spins, creating a potentially never-ending loop of free spins. In practice, this seldom happens, but it is possible to get a couple of consecutive retriggers in some games. It’s also worth noting that for many games, a sequence of scatter symbols also holds the key to unlocking the jackpot, so this is always where the best of the action is to be found.
5-Reel slot machines are the most common type found at online casinos, offering five vertical columns, each of which usually contains three to four rows of symbols. You will also find a smaller number of 3-Reel slots. These are usually simpler games that more closely resemble the Classic Slots one might find at a pub or arcade.
Video Slots refer to slot games that use a graphical interface rather than mechanical wheels. These can be found in land-based pubs and casinos as well online. The term can also be used to differentiate between modern, graphically sophisticated online slots and “Classic Slots” that ape the simple looks and mechanics of traditional fruit machines.
Free Spins refer to free turns that are received as part of a bonus feature of the game, or to free games that are given by online casinos to entice new players to make a first deposit.
Progressive Slots like Mega Moolah and Playtech’s DC Superhero line of titles are perhaps the most popular of all online casino games. Why? Because their linked jackpot prizes build up every time someone plays the game – at every single casino site that carries it. That can lead to some life-changing seven- or eight-figure jackpots!
Random Number Generator (RNG) programs dictate the outcome of every online slot game (and casino games like roulette and blackjack, too). They ensure that the result of each game played is truly random, and that each title adheres to its advertised average payout percentage (see below).
Multiplier features are commonplace in online slots. They are usually activated as part of a bonus feature of the game, and multiply potential winnings by a set amount. Without unlocking multipliers you usually won’t win a game’s biggest prizes.
There isn’t any advice we can give that will improve your chances of winning at a particular slot. Success is all down to chance, no matter what anyone else tells you. However, there are two key pieces of information – payout percentage and variance – that can tell you a lot about your likely experience with a slot game, at least over the long-term.
Where slot machines broadly differ, other than in their theme and design, is on the question of payouts. Generally, you’ll find online slots paying out at between 92%-97%, with a few outliers on either side. What this means is that the game has been set to pay out this percentage of its takings over time. This is representative of the house edge built into each game, so higher payout percentage games are naturally more favourable to players in terms of the odds on offer.
Given that players have very little influence over the outcomes in slots, beyond good luck, it makes sense to look for games with higher payout percentages – also known as ‘Return to Player’, or RTP percentages.
Slot can also differ in terms of volatility. Think of volatility like the temperament of the game. Some slots are steady and consistent, whereas others are wild, with violent swings between losses and wins.
Two games with the same payout percentage can feel radically different for players depending on their variance. A low volatility game will pay out small, regular wins, without costing too much along the way. A higher volatility game can suck in money rapidly, but will pay out much higher amounts when you win. Players will have their own preferences, but for the most part, you’re safer with lower variance games – even if you are limiting your potential take.
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