How to Play Online Slots

how to play slot machinesSlot machines are the most popular casino games since 1899 when inventor Charles Fay assembled them. The turn of the new millennium saw the digitization of casinos into online internet sites, and hence more and more IT startups developed web slots.

These are slot machines which are in a digital version, playable on electronic devices such as mobile phones, PCs, tablets, iPads, iPhones, and even laptops. Online slots, or pokies as they are known in Australia, have replaced the randomness of mechanically stopped reels with random number generators (RNGs).

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In other words, it is the RNGs in slots which determine where each individual reel stops, and this way, it is possible to make a line of symbols which influences the payout. Another fascinating feature of modern slots is the paytable which calculates each combination of symbols to ascertain the size of the win.

In most cases, if a player matches the rare symbols across the reels, then the size of the win is usually higher. We take an in-depth look at these and more features below.

How Do Slot Machines Work?

how do slot machines workOnline slots still use reels to determine the result of each spin. They are referred to as virtual reels and are mostly in sets of 5 symbols on modern slots. Their similarity is reminiscent to the classic slots found in brick and mortar casinos, although these usually had 3-reels only.

The basic functionality and gameplay are the same, with a few underlying factors mostly related to their design. One on hand, the classic slots of yesteryear were purely mechanical, while the modern-day slots are purely digital.

They are virtual representations of the old yet a common trait is that the reels stop at random positions to determine the outcome – win or loss. It is a trait that makes slots among the more easier games to play at any casino and it is evident just by gauging their popularity across the globe.

Why change something that has worked fine for years, right? Well, in all honesty, something has changed since the turn of the new millennium. Back in the day, high rollers used to walk in with large tracts of cash and sit within the casino for hours. The classic slots relied on mechanical stops to create randomness or a sense of luck.

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What is Random Number Generator (RNG)?

Today, by using advanced technology and Mathematical ideologies, developers of these virtual casino games have redefined random outcome in online gaming. All fair slot games have the outcome of each play based exclusively on a random number provided by a Random Number Generator (RNG). This random number generated, “tells” the reels when to stop and thereby determining the outcome of the game albeit randomly.

In essence, it means that if the same game generates the same random number in another instance, then it must always give the same outcome. Simply put, if the random number generated is X, the wager B, and the win Z, then in a similar random circumstance, if all these figures remain constant, then the outcome (win) must be the same.

This is why there independent third-party auditors such as eCOGRA, who put the slots through various tests. Among their core focus is the RNGs. They repeatedly test the slots to determine that if the RNG is kept at a constant, whether it will give the same result again and again.

slot machine how it worksIf it does, then this means that the slot is credible and does not rob the player by mostly understating the win amount, or lowering the ratio of the wager vs. the win amount (outcome). In a more concise look at how RNGs work, it should be noted that the theory is Mathematical, which is how the probability of a win or loss is determined anyway.

It is All Mathematics!

The game’s mathematical module takes the random number and calculates where the reels should stop which is further proof that the outcome is not pre-determined by the casino. After this, the game stops the reels at the determined positions and calculates the outcome of the spin after which the outcome of the spin is then displayed to the player who initiated the spin.

So as you can see, the outcome is as a result of ‘luck’ because the casino personnel do not control the slots neither is it influenced by your previous loss/win or that of other players as well. An interesting fact is that the RNG software installed generates thousands of random numbers each passing second, so every time you press the start/play button, you automatically change the outcome of the next round, even if it is just a second later.

The bittersweet side of this is that you won’t know whether the outcome will be better or worse until the results are displayed on the screen. Some of the features of a slot game that define its outcome are factors which include; the win size in the pay-table, the sets of symbols on the virtual reels, the settings of all bonus features, and the rules plus probabilities of these bonus features.

What is Return To Player (RTP)?

Apart from RNGs, we also have RTPs. An RTP is the Return To Player ratio which simply describes the percentage of the staked cash that the slot machine will payout to the iGamers over time. For instance, if you place 100, $1 bets on a slot on which the RTP is 80%, you might get back about $80 in wins.

This has a direct proportionality to the house edge and in most cases, it is calculated over the long term rather than the short term. The reason is that when staking online, anything can happen in the short term and one of the common practices of online gaming is that it is always advisable to bet with money that you are prepared to lose.

So, if the slots have a 25% house advantage then it means that their RTPs are 85%. The house advantage is also known as the house edge, and it is the amount of money that the online casino is presumed to make every time an amount of money is staked by a player. At an 85% RTP, this implies that the slot will keep about 25% of all the money that has been wagered and 85% will be returned to the players as wins over a period of time.

slot machines how they workAnother term that is closely associated with the RTP and RNGs is the hit frequency. It is a term that casinos often use to describe how often digital slots land a winning combination. If we say that it has a hit frequency of 7%, then it implies that the slot will always land on a winning combination about 7% of the time.

How To Play and Win on Slots?

You should also note that most slots enable players to stake on multiple lines for every single spin. The outcome is such that, on a single spin, a player can either land one or more winning, or losing combinations. It might feel to the iGamer as though there are more wins, but over time the losing combinations might outnumber the winning ones by far.

Since slots payout at various rates, they can be classified as either low, medium, or high volatility categories. A slot’s volatility somewhat relates to its RTP where high volatility means that you are more capable of winning higher amounts while wagering lower stakes in a much shorter period. With lower stakes, you end up losing less, statistically speaking.

The effect is that a low volatile slot pays out frequently and even if the slot has a lower RTP, you still have a better chance of landing a decent amount, although on many/cumulative wins. It is often stated, that when not taking into account the lottery games, it is the slots which are the most volatile types of games that you can play at a casino.

Their high volatility is the reason they are so popular, because wins are never that far apart. In fact, there are tips that are said to slightly affect a slot’s volatility which means you can win a big enough amount.

Usually, after the first stake, a player is advised to double up on the wager or alternatively, change the number of paylines to 1 and increase the bet per line. In the second instance of increasing paylines, there is a much lower chance of hitting a win, but if you do so, the wins are much higher.

Just remember that the core component to a slot’s functionality is the RNG. It has a direct bearing on the hit frequency which is why Progressive Jackpot slots have wins so far apart. Their hit frequency is so low that it makes it more difficult to land a jackpot win.

Online Slot Machines Programming

online slot machines programmingEach player might have a liking of a different slot title. Sometimes, because of this, players like to indulge in these same slots over and over. It is probably one of the reasons why developers who focus solely on creating casino games were established.

They are mostly independent companies that develop casino games using custom themes as well as a wide range of gameplay features. These gameplay features, which might vary depending on the developer who created the game, are the basis of programming.

You must note that digital slots are just but software which has been programmed to create an outcome or result which can either be classified as a win or a loss.

This is briefly how it works:

1. The casino initiates your gaming session, then your internet browser communicates with the servers of the respective game provider.
2. The random number (RNG) plus the outcome of the round is also generated by an independent company which in this case is the game provider. All the casino does is just to confirm your stake or bet while confirming your transactions beforehand.
3. The server of the game provider uses the generated random number to spin the virtual reels while calculating the outcome of the round.
4. The result or outcome is communicated to the casino by the game provider.

From here, the casino will then credit your player account in the event of a win. If you lose, then the casino keeps your debited amount. What is fascinating, is that this happens in under 250 milliseconds of pressing the play/spin button from your browser.

What Are Your Chances to Win?

What you need to understand about the programming, is that there is a definite chance of landing a win, even though it is not guaranteed. Before licenses are handed out to casinos, they must prove that their games have met the international standards and one of the focus is that they must not be biased.

So, if you lose while playing a slot, then it means that you are not lucky and probably, a few more spins might change your luck. The RNGs, RTPs, and hit frequency information of a slot help players in determining just how lucky they can possibly get.

programming of online slot machinesFor instance, an RTP below 50% means that you might have to play more spins to land a win than if you did so on a slot with an RTP of 80%. They are basically programmed in the language called Java. These programming languages are such that they produce the random numbers for each event played by the gamblers.

Software engineers in the iGaming industry program and design slots that are playable by any interested party and do not limit the slot designs to a specific audience. Unlike other casino games such as Poker or Blackjack, there are very few rules if any, attached to the gameplay.

It is one of the reasons these games are so common and even inexperienced can play them for fun as a free trial, without wagering real cash. A wide range of consulting is done during the developing and programming phase of creating slots.

A Mathematical algorithm called random number generator is written and this generates the random number irrespective of the inputs provided by the gambler. It is based upon a myriad of factors such as timings, stake, and paylines among other parameters.

Who is Programming the Slot Machines?

Programming is carried out in the IT (developer) hubs where there is a secure environment and the functionality plus designs are not exposed to the outer world. If such sensitive information were to leak it would make it easier for hackers to manipulate the algorithm to their advantage thus raking in big wins.

This would drive the casinos to huge loses since they would have to pay out the wins to the respective players. Alternatively, if the same manipulation was to be done by the casinos, then it means that they would reap huge profits.

To better understand slot machine programming, you need to know that the Random Number is an input which can be anything like a sequence of dates, weeks, days, months, years or just a timestamp of up to 6 decimal places.

programming of slot machinesSometimes during programming, a random number itself can be used as an input to generate another random number while having some calculations within it. Another theory is that a slot machine can have bugs which might inhibit the normal functionality of slots.

It might arise from errors during the development stage which is why it is always advisable to play at reputable casinos which have state of the art SSL encryption for security purposes. If a slot has a bug, this means that it does not function as it should and at times even a third-party can manipulate the outcome such that you might end up losing even when the outcome should be a win.

Online Slot Machines Providers

Some of the top programmers or developers in the market who create some of the best slots include the very reputed names include 1X2 Gaming, NetEnt, Bet2tech, Betsoft, Microgaming, Novomatic, Gaming Evolution, Playtech, and Pragmatic Play among others. These providers design and create the slot machine and then market them to most online casinos.

There are a few establishments who develop their own custom games, which can only run on their platform. Other companies such as Playtech, Novomatic, NetEnt, and Microgaming have been around for decades, and boast an extensive portfolio of online slot machines dating as far back as before the year 2000.

There are new players in the industry such as Yggdrasil, which have a couple of slots that are fast becoming a fan favourite. The better you understand about the programming, the easier it becomes to select slots.

Slot Machines Features

slot machines featuresWhen it comes to online slot games, there are terminologies such as Wilds, Free Spins, Scatter symbols, different ways to win, bonus spins and Multipliers. If you are a beginner, then this casino terminologies might seem hard.

Whether you are an enthusiast or you just enjoy the simplicity of the spinning reels of slots, then you must know that different slots all have unique features. Some need further elaboration to give you a better understanding.

Different developers implement these features differently. Some slots have a unique feature that you won’t see on others, known as – Megaways feature. It allows players a variety of ways to win. This article defines unique slot features, some of which are only exclusive to 5-reel video slots or classic 3-reel slots. Additionally, there are other notable features offered by other developers.

  • Paylines On Slots – the word paylines might confuse beginners, but its definition is actually quite straightforward. Paylines are simply the winning combination that can be made on a slot machine, ranging from 20 or 25, to a whopping several thousand depending on which slot you are playing.
  • Classic Slot Feature – it is mostly on 3-reel classic slots, which are reminiscent of physical slot machines found in brick and mortar casinos. They are more common among much older players, who frequented casinos before the turn of the new Millennium. Such slots are easy and straightforward to play, plus they seem to never become irrelevant among the casino enthusiasts.
  • Coins & Coin Sizes – in online gaming. it is the coins which are used in placing stakes on the slot machine that you are playing. It is the coin size that determines your stake and the payout. The larger the coin size on your stake, the higher the payout.
  • Return To Player (RTP) – it is a feature that is completely in the control of the developer while they create the game. Similar to volatility, the RTP will always be stated before playing the slot game. RTP can range from anywhere between 80% to 97.5%. The higher the RTP, the lower the volatility on a slot machine is.
  • Progressive Jackpots – they were common in mortar and brick casinos. When a casino has a number of such slots, then the collective or cumulative loses are pooled together into a jackpot, and only one lucky player can win it! Most casinos offer at least a single progressive jackpot slot.
  • Volatility – it is more of the mechanics of how the slot machine functions. Usually, the lower the volatility, the more the wins for the player but the lower the payout is when the iGamer manages to match the symbols on the reels for a winning combination. The lower the volatility on a slot, the more frequent the wins are, but the less the player will get paid out.

Video Slot Specific Features

video slots featuresVideo slots have far more features these days compared to the old classic 3-reel slots. From Stacking Wilds symbols to Reload Bonuses, to different ways to wins, players are spoilt for choice considering the various features found on slot games.


Free Spins – it happens to be one of the popular features on slot games, even in both classic and online video slots. They can be gifted to the player via different means, usually depending on the slot type. When it comes to classic slots it means that landing a particular symbol in a similar manner but on video slots, this means landing the scatter symbols.

Free Spin Re-Triggers And Re-Spins – in as much as they seem different, both these definitions are somewhat similar. Both re-trigger the bonus rounds which sometimes result in huge wins. Players can retrigger a Free Spin round or a bonus round by aligning specific symbols or landing combinations.

Wild Symbols – these are, in some way, like pulling a Joker card similar to when you are playing a game of cards! Wild Symbols work exactly the same way in that they can be substituted for any symbol while increasing the win chances for the player.

Scatter Symbols – they are specialized symbols which stand out from the rest of the paytable symbols. They usually come with a specific function attached which enables the iGamer to progress to the bonus round (Bonus feature or Free Spins round) from the base game of a slot.

Stacked Wild Symbols – they are almost similar to Wild Symbols on video slots, with similar functionality. These symbols mimic the adjacent symbols. When it comes to the Stacked Wild Symbols, you can stack them on each other. They can cover the entire reel vertically, which means they can be 4 or more, depending on the reel’s height.

Ways-to-Win Features

ways to win featuresThere are a couple of Ways To Win features, each being specific to a single developer. Even though they are not very common in most slots, you will find them often.


  • Win Both Ways – it is a feature that allows players to match combinations on the reels, both ways. Normally players can only utilize combinations made from left to right on the reels. However, this feature goes both ways, thereby increasing chances to win.
  • 243 Ways To Win – this is the first of the features to be created and used in digital slots. Slots that have these features enable an iGamer to get a winning combination of up to 243 different ways, thereby improving chances to win while getting a higher payout as well.
  • 1024 Ways To Win – this is an upgrade from the 243-Ways-To-Win feature. It is played on any online slots with at least 5 reels or more, making it possible to combine various symbols into a large number of winning pay lines.
  • Megaways Feature – it is almost considered as the more superior of all the Ways to Win features. It is a slots technology which has been pioneered by Tiger Gaming. It also happens to be one of their biggest trademarks. This Megaways feature allows close to several thousand winning pay lines which guarantees some big wins.

Slot Machines RTP & Volatility

slot machines rtp and volatilityBoth RTP (Return to Player) and Volatility play a vital role in slot machines, so understanding how they both affect your gameplay can help you come up with a strategy. All slots have different volatility levels, and comprehending how to use both RTP and volatility to your advantage, can help win you money and prolong the game play session.

Volatility, in other words, means the level of risk you incur that might determine if you lose your bet when wagering. Alternatively, it might influence just how much cash you can win in the long run on the online slot machines.

The slot game that you are playing might have a medium, high, or low volatility level, each of which comes with various benefits that you can use to your advantage. It is without a doubt that as an iGamer, you always strive to land more wins while you are gaming online.

So it is no surprise that you are probably searching for slots with a low-risk factor. Most iGamers avoid slots with high-risk and prefer the ones with a low-risk. However, in online gaming, developers, as well as some experienced iGamers, still prefer high volatility slots.

Different Players, Different Volatility Levels

Different players play slots with different volatility levels for a number of reasons. We all know that low volatility slots pay more often, but the huge wins are in the slot games with high volatility. The Low-risk slots will pay often, but the payouts are much lower. Alternatively, high variance slots do not pay regularly but payouts tend to be on a larger scale.

The variance type that you should opt for relies on a few factors. Ideally, it mostly depends on the gaming thrill that you are after and the amount of money that you are willing to stake, plus the game’s RTP. The RTP (Return to Player ratio) is usually expressed as a percentage. A majority of digital slots have an RTP that ranges anywhere between 94% to 98%.

There are creators who develop slots with an RTP that is slightly higher than others although the difference in percentage is usually less than 5%. The RTP is applied to a particular number of spins where it is a theoretical value that indicates how much the players can actually win and the amount a casino retains.

slot machines rtpThis does not imply that if there is an RTP value of 98% on a slot, you should win back 98% of your bets. It is not surprising that, that RTP in some way, has an effect on the slot games’ volatility. It is a variance which decides any differences in both the theoretical RTP per single session.

It is due to this reason that the low variance slots often deviate from such a percentage because of small payout amounts, although regularly. If you opt to indulge in online slot games with high volatility, then this implies that they will probably vary.

For instance, if you happen to spin the reels 10 times and you don’t win anything, then the RTP is calculated as 0%. But, if you make more spins, then you should brace yourself for a decent payout, eventually. Considering that you land a win on your 300th spin, then this translates to 1,000x the initial bet albeit with a calculated RTP of about 333%.

High or Low Volatility?

It is quite an achievement when compared to the theoretical RTP as indicated by the developer. This is the reason that high volatile slots usually have lower RTPs. Wins are much far apart, but when players land a win, it’s quite huge by usual standards. Low volatile slots which often pay out, happen to be the most popular type of slots and they usually have high RTP.

Though payouts are somewhat smaller, they will occur more regularly. Generally, it gets you playing for a while and you can continue pushing your luck by using the frequent winnings. Medium Volatility slots can land both big and small payouts and they always alternate at times.

Spinning the reels will land you a win more often but it will be at a lower frequency compared to low volatile slots. At times it can be somewhat frustrating to players because it is somewhat difficult to be sure when to expect a win. However, they are more ideal for iGamers who prefer a little more excitement compared to that of low variance slots.

It is also recommended for those players with a large cash reserve to spend. If you prefer to indulge for a while longer, then medium variance slots are more suited. As for High Volatility slots, these they are both fast-paced as well as high risk. A slot game with high volatility does not payout regularly, but if you do win, it will be a large amount.

Money Management

slot machines volatilityYou can spin the reels for a while without winning but if you do, it will be significant. Such types of slot games require you to use a lot of cash, to keep you playing since there might be tough times ahead. Such information is highlighted on the slot’s pay details section of the slot. It is best to always do some research even before spinning the slot’s reels.

Once you have checked the volatility and RTP, only then can you create a strategy. If you opt for a big win, then forget the low volatility slots. It is essential to remember that the longer you play, the more you might lose as a result of the house advantage.

Ensure that you have a budget plus a pre-set loss limit especially when indulging in medium volatility slot games. There is a myriad of strategies that can be applied depending on the volatility levels. It is important to know when to continue playing and when to stop.

Note that high-variance slot games will run through your money much faster. So, always make sure that you have a significant amount, which is enough to keep you spinning the reels even without a win, for a long duration.