Online slot game – the modern twin of an old fashioned one-armed bandit. With times changing and popularity of online casinos on the increase year by year, the twist on a classic one-arm bandit is taking over the modern world by storm.

Game developers work hard every day to test, develop, and introduce new online slot games to the ever-increasing library of both landbased and online/ mobile casinos. Not only the features but the theme, graphics, music, the feel, and amount of reels and different jackpots are some of the few characteristics of what makes the game special and adds the little ‘extra’ to ordinary.

We’ll try to describe to you in a bit more detail – what is an online slot, walk you through some of the main types of the slot games and give you a brief overview of rules, bonuses and the main terms and definitions used with relation to online slot games, plus casinoexplorer team will dive a bit into the most common myths and urban legends surrounding the online slot games.


Online Slots

So how, where and what are the slot machines?

Online slot games are currently the most popular type of games played in casinos, both land-based and online. Of course, because of the core of our site we ‘ll focus more on online slots to help all the players reading this understand a bit more about the mechanics and how has it all started.

Many different casino games have common roots and their history reaches hundreds if not even thousands of years back with the first card and dice games way preceding Roman Times, but with online slots the situation is a bit more complicated as its one of the newest types of casino games.

The Urban legend says, that one of the first one arm bandit/ slot game/ slot machine, as we know it now, was first developed in Brooklyn New York around 1891. It is said that a company of Sittman and Pitt were first to design a machine that was a great-great-grandfather to modern slot machines. It was designed using principals of poker games and built with five drums each containing 50 cards. The machine had a type of a window display that was showing the end position cards in the visor, based on the combination of cards displayed the reward was calculated, a century later and we have thousands upon thousands of variations of a Sittman and Pitt slot game.


As mentioned a few times previously the types of slot games go into hundreds, and for sure we won’t be able to cover them all in this article, but I’d like to introduce you to few of the most popular and well-recognized types of casino slot games:


Slots with multiple reels

multi reel slotsOriginally in the classic one arm bandits, the standard was for the slot machine to have 3 reels, but in the modern, especially the online 5 reels became a modern standard. Saying that we know that by no means it indicates that all of them have 5 as the imagination of developers and expectations of players rise every year, therefore now we can easily find a lot of slot games that have 6, or even 7 reels. Some of the reels work as standard reels in the classic slot, but many of them play additional role awarding special bonuses, winning combinations, increased jackpot potentials, multiplayer and more. Even though that seems like a great idea and ‘more is better’ majority of players still consider 5 reel slots to be a standard and most sought after option. Therefore as you can guess, they still are the most popular type.


Slots with multiple pay-lines

multi payline slots

Paylines are the lines that indicate the placement where winning symbols need to align for the reward to be given bonus awarded. Originally we only had horizontal pay lines but in modern slot machines and online games, we can have multiple combinations of horizontal, vertical or even a random combination of different positions, the more pay line options in a casino slot game the more chance to be in it for some money, free spins or an additional bonus of some kind.



Progressive jackpot slots

progressive jackpot slots copy

This type of slot game is becoming more and more popular especially among players that like playing online lotteries. Not that we can compare playing an online slot to playing an online lottery, but if we are lucky and we hit that sought after jackpot it really can be a life-changing prize!

The jackpot in these types of slots is increasing progressively with more players involved and using the slot over a long period without cashing out. Ideally, and to be able to rack up a really large number the slot game has to be played for quite a long time and the average spin value should be kept at the higher end of the scale. On progressive jackpot, a lot of players spend months just to hunt that big prize, and man is it worth it when you win


Slots with bonus rounds

bonus rounds slots

These are the online slot games, that offer you bonus spin rounds. They are usually very popular as give you that bit extra excitement and opportunity to hit some fantastic bonuses while chasing the main prize





Of course, there are different ways that we can categorize slots and online casino games:

  • Slot games for real money

    as the name suggests these are the slot machines in both land casinos and online that use real money for play. So you set up the amount for every spin and can enjoy the game


  • Free Slot games

    Free slot games are usually the machines or slot games that don’t require any payment to be able to play. Sometimes these are the demo games, or demo versions of the actual slot so the players can test which is not always a full version of the end product. But on the majority of occasions these are fully developed games that are free to allow players to discover the world of online casino games and to see. If they want to play for real money.


  • No deposit slot games

    Usually in the form of free spins (that work per amount or have a time limit) awarded by the online casino in the form of seasonal promotions or bonuses. Gives especially a new player a great opportunity to check out the casino game without risking their own money and at the same time to be in a chance to win some, how do we call it -> WIN-WIN ?!


One more classification that I will mention quickly will be based more on the graphics and feel of the casino game rather than the monetary value, or a chance of winning.

classic slots

Classic slots

This is the type of an online slot the closest based in look and feel to the typical old school one-arm bandit. It has very similar ‘mechanics’, symbols, pay lines, and reel amounts. You cannot really ‘win’ with a bit of classic feel in a casino game can you?



video slots

Video Slots

Video are quite a new invention of the casino game developers. The most standing-out feature is the quality of graphics and music that works towards us immersing more into the game plus additional features make us feel sometimes like we are inside a movie.



3d slots

3D Slots

These are the newest inventions in terms of casino slot games developed. Long story short as everyone can guess what differentiates this type of game from the other slot machines is the 3D graphics that try to immerse its players even more into the game world.



By no means and in no shape or form, we have exhausted all the types of slots but at least I hope we were able to expand a little bit on main differences that we can find when we first approach an online casino with the lookout for our guilty pleasure for next few hours.


Online slot games main rules and lingo

One of the reasons why playing online slot games and slots is so popular is probably the simplicity of the whole process, and general lack of strict rules or the importance of  ‘know how to’ as we have it in such games as blackjack, poker or even roulette. In online slots all we have to do after we pay in deposit, we want to play with, or use one of the free games is set the amount we would like our spin to equate to, press the button, or click on the spin button and wait for its paylines to align (As always casinoexplorer team encourages every player to be gamble aware and play responsibly, always gamble only with the money you can afford to lose, we only want you to have fun and enjoy yourself. Winning money is absolutely a bonus but it should never be a goal!).

After we start the game the reels start spinning and depending on the type of slot and game we play they will end up in different combinations, that will provide us with a win, free spins, additional bonus, or if it’s a miss we have to spin again and keep those fingers crossed for the right combination to show up at the end.

We have to remember as well that in most cases different symbols have different values, both in bonus that we can win and in the monetary value. Below we will try to explain a few of the most popular that you can come across playing online slot machines.


  • Free Spins – free spins I dare to say is one of the most popular functions, bonuses that modern casino slot games have implemented. Sometimes we can start the game with a certain amount of free spins that have been awarded during our sign up or as a part of any other casino bonus, and of course they can be won in the course of the game. Casino slot games award you free spins when specific symbols align in a certain manner typical for specific games, but they can be as well activated completely randomly by the system or awarded after a certain amount of gameplay time.


  • Wild Symbol – Wild symbols are special symbols that we can come across during a wild spin. If we see this kind of symbol during our online slot spin he will automatically fill in the gap if we are missing any other symbol from the set that normally would be needed to win a prize, so kinda like a joker that jumps into any suit that we need at any given moment. Especially useful if our cluster payline has 2 out of 3 winning symbols – wild will then jump in like a chameleon transforming into a complementing one, and the bonus is ours.


  • Sticky Wild symbol – Quite similar to the one above ‘regular’ Wild symbol, the difference is, the normal wild symbol only shows up and works for one spin, the Sticky Wild – well it remains sticky while the other symbols start spinning in the reel. and stays on the screen to be potentially used in the next one, giving us an additional chance of winning the bonus.


  • Stacked Wilds – is a relatively new feature in online casino slots. They work very similarly to the regular wild symbol but usually, they don’t only substitute one other symbol to help us with the win, but depending on the game and set up, they can fill out the whole payline, or a reel giving us that much more of a chance to win.


  • Expanding Wilds – another symbol that can work instead of other regular ones. When the expanding wilds symbol shows up in one of the clusters it starts expanding to neighboring ones after reels stop spinning.


  • Random Wilds – It’s a random feature in some of the online casino games when random wild symbols pop up on the screen after the reels stopped spinning and round is in theory over.


  • Scatter Symbols – sometimes referred to as players’ best friends. In general doesn’t have to be lined up, or in any general order, just a mere showing up of certain scatter symbols on the screen activates a special bonus, or an additional feature.


  • Jackpot – jackpot, in short, is the ‘big kahuna’ of prizes! If we manage to hit a special combination of symbols we hit the JACKPOT which indicates the highest winning for that particular slot game that we are playing at any given time!


  • Progressive Jackpot – explained briefly previously is similar to jackpot but the amount is decided by the players, and being more specific it’s dependent on the amount that has been put in the slot previously by the players. It accumulates! But if you hit it! Yachts, Ferraris and private jets (ok I got carried away-but you know the drill).


  • Autoplay – is just a function in an online slot game, that allows us to set up a certain amount of spins and amount of bet that should go for every spin. After we choose that we press play and the game will do the rest, we don’t have to press after every spin.


I thought it wouldn’t be fair if after all that I wouldn’t mention at least a few titles that proved to be very popular recently coming from various software developers

Starburst – Starburst was developed in 2013 and since then has been one of the most popular and successful slot games not only from the Netent provider but in general in online casino slots genre. Starburst is a classic slot very colorful and dynamic that brings a lot of energy to the game.

starburst slots game


Mega Fortune Slot Game – Another product from the powerhouse that is Netent. This slot is number one on the list of progressive jackpot slots and you remember when I mentioned the yachts, Ferraris and private jets? Mega fortune slot has left its mark in World Guinness Book of  Records when in 2013 a lucky player has won a whopping 17.8 million euro. The whole slot and graphics are oozing fortune, fame, and glamour – symbols are being represented by champagne bottles, yachts, and other items associated with fortune! Not only the symbols and the name but for real, mega fortune stays since the beginning till now one of the highest paying online casino games of all time!

mega fortune slots game


Mega Moolah – Another progressive jackpot slot this time from the stables of Microgaming is Mega Moolah. Created over a decade ago doesn’t age you could say as still stays popular mostly thanks to the attractive jackpots that are on offer. And we have 4 different ones in this slot game :

  • Mini Jackpot
  • Minor Jackpot
  • Major Jackpot
  • Mega Jackpot

The mega one starts at about 1mil euro and is progressive so we know that the number constantly goes up!

megamoolah slots game


Gonzo’s Quest Slot – Just like with starburst if you ever heard about online slot games for sure you have heard that Name and probably played a bit as well. The stand out point for Gonzo is its graphics and story that takes you to South American Jungle in the search for the mythical Eldorado the city of gold! Fantastic features, great graphics, and the captivating story make this slot top of the list year on year!

gonzos quest slots game


Book of Ra Delux – Novomatic hit the jackpot with this Egyptian themed slot, it has become popular from the get-go and stays as one of the most enjoyable online slot games and one of the best in terms of average payouts.

book of ra deluxe slots game


Very difficult to stop here and not list more and more as there are tens, well hundreds that casinoexplorer would love to mention and share with you, but probably better if we dedicate some part of the site later for you to stay up to date with the best casino games.

As we promised in the beginning casinoexplorer team will try to answer some of the myths and chatter that has been circulating one arm bandits and casino slot games:


When we play using casino bonus/free money that will decrease our chances of winning in an online slot game.

Not true

even thou you’re probably right casino would prefer if you bet some of your money instead of giving you a chance to win without any chance for the house win. But to cut it short no not true online casino game doesn’t know if you play with your own or with bonus money, so as per usual the outcome is completely random.


The longer I play aka the longer my losing streak the more chance I have to finally hit that jackpot.


the Random number generator is what it is it is random so you may play 200-300 spins without winning and not hit a win till 400-500 or you can hit the jackpot in your second spin.


Hot, or cold slot!

Not even close to the truth

. I think especially in the movies we’ve all seen the stalkers lingering around that one specific bandit with one arm claiming that word on the street is this particular machine is hot and gives often and big payouts. Truth is all the slots, land-based casino slot machines and online slots use Random Number Generators and the odds of winning are always random.


Please find below some of the casinos carefully chosen and recommended by casinoexplorer team especially thanks to a great choice of slots, and games providers.


Slots FAQ

Can i play slots on my mobile?

Yes, all the casinos listed on casino explorer have mobile versions of their site with large libraries of online slots available to play on the mobile devices. The amount of games may differ from the desktop, but operators are regularly updating the library of games available for mobile players.

Can i play slots using Rand?

Yes all the casinos that we list on our site and feature online casino slots allow you to play with South African Rand without any need for conversion!

Do i have to play slots for real money?

No, you don't as majority of the online slots available have a free play option where you can test the games first and see if it's something that tickles your fancy. On top of that there are many bonuses available across different online operators that award you free spins sometimes even without deposit. For more info head to our free spins page and choose the casino to play!

What is the most you can bet on a spin in a slots game?

It really depends on the game and casino, but you should always see the info how much is it possible to bet on single spin. Remember that some casino bonuses may put a minimum or maximum limit on the spin to be able to be eligible for the bonus. So always remember about terms and conditions..

Is playing online slots safe?

As mention before with regards to online casinos safety and security stays on top of their priorities to make sure all the players financial and personal information is always secured. Online gambling industry is a very strictly regulated one and is a subject of regular compliance checks, therefore, you should feel. For more info and licenses of specific online casinos please have a look at our online casinos page.

What is the best strategy while playing online slots?

There is no real way to apply an effective strategy that will guarantee us winnings every single time, as a all the spins and bonuses winnings are random and it is a game of luck. What you can influence thou is the amount you spend being your bankroll management, and your choice of online casino, bonuses acquired and game you select to play, as they all vary in features, bonuses and jackpots.