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Online slots and their main features

Published by Niki | April 24, 2018 | Last updated: May 25, 2023

A brief history of slots

Back in the old days without online casinos, slot machines were only found at land-based casinos and certain pubs. You could pop your coins into the machine and pull the lever arm at the side of the machine to roll the 3 reels for the chance of matching traditional ‘fruit icons’ or big ‘red sevens’ along a single payline, to win a cash pay-out.

Those ‘one-armed bandit’ type machines have now mostly been replaced by more sophisticated machines, that run on electronics with processors and digitally mastered reels on the screen, to provide a far more progressive gaming experience.

The modernised programs have allowed for gaming to become far more versatile, offering the player more than just the run of the mill reel roll – they now offer special features and some more complicated bonus rounds. CasinoWow offers wide-range of casinos, information and help for responsible gaming.

What are online slots?

With the advance of the information age, the whole world has focused itself on the internet. It only stood to reason, that sooner or later the gambling industry would take advantage of the ‘Worldwide Web’ for profit and gain; after all, the internet can most certainly reach more users than any single land-based casino ever could. With the internet age, has come the ‘Instant Age’, where people want convenience at the click of a button, now!

Online slots are an answer to the trends of this age whereby iGaming developers are reproducing many of your favourite slot machines, with the addition of many more titles. These can be played from your desktop, and in many cases, your mobile device, from almost anywhere in the world.

Play from the comfort of your home, during your lunch break, or while waiting for the train, online gambling aims at entertainment when you choose it. Flash players and HTML5 technology have opened up the gambling industry to a number of users that would never have had the chance of this type of entertainment before. It offers you the chance of winning while on the run.

Online slots and their main features


In the online slot segment, there are literally thousands of games available for playing from an array of slot providers, such as industry giants, Net Entertainment, Microgaming, IGT, SGI, and many, many more. Themes available in the online arena include:

  • Classic Slots – These are the most basic machines, often encompassing only 3 reels, and offering very few special features. It’s the way slots were formed in the beginning.
  • 3D Slots – These are slots that have moved away from traditional 2D graphics to provide something more astonishing and upmarket.
  • Vegas Slots – These are the online slots that resemble their land-based counterparts found in Las Vegas and other such places.
  • TV & Movie Slots – These slots are made in homage to famous TV shows or films.
  • Holiday Slots – These are made to honour the variety of holiday seasons celebrated around the world, such as Christmas, New Year, Valentine’s Day, Halloween, etc.
  • Progressive Jackpot Slots - The jackpot on these slots grows as betting increases throughout the entire network.

Check out the variety of slots directly here:

The above categories are just the start, but as you can see, there is a slot theme for every taste, and encompassed within these themes are genres ranging from horror, to action, to adventure, to animation, to fruit slot, to sci-fi and more. No one has an excuse for being bored.

How slots work

By loading credits into the machine, via your online wallet stored in the online casino, you are able to bet on the next ‘reel roll’ which may or may not land you a combination win and cash pay-out. Certain symbol values differ from others, so the pay-out for matching various symbols will differ based on the icon you have matched.

Keep in mind that often the least number of matches you can make on any one payline is usually three, with the most usual being five. On a five-reel online slot, if you match 5 of the highest paying symbol on a given payline, you will win the ‘jackpot’ or top prize. This pay-out can vary from 10 times your stake to multiple thousands of times your stake, depending on what game you are playing.


A reel is one of the vertical columns that carry the game icons/symbols on them. When you press spin, it is these that roll at speed and stop randomly to produce the ‘hand’ for that particular wager. Reels can vary from 3 across and 3 high to 12 across and 12 high (colossal reels), but the average reel set is usually 5 icons horizontally by three or four icons high.


A slot payline is a predetermined pattern set on the reels. If you land matching combinations across that line (usually from right to left), the game will pay you for a win. These paylines can run horizontally and diagonally in both straight lines and zig-zag fashions, across the reel set.

Different games have varying numbers of paylines. Titles can range from set patterns of 1 payline to 100 paylines. There are even certain titles that adopt the multiway payline feature, which can offer you between 243 to 117,000 ways to win. Here, instead of set patterns, wins can be made if matches merely occur by the same symbols occurring on reels adjacent to one another.

There is also a difference between fixed paylines and varying paylines. With the former, you are forced to bet on all paylines available, and on the varying paylines, the amount you choose to wager will determine how many paylines you bring into play.


To be able to spin the reels of a slot machine, you will need to ensure that a bet is first placed. This can be controlled on the interface of the game. Be sure of whether you are playing a fixed payline game or not, as this will affect your total wager. You will need to be cognizant of the fact that the more you bet the more you can win, but on the other hand, the more you can lose too. It may be a wise decision for you to read up on our guide on “Online Slot Strategies”.

Bonus rounds

With the increase in competition in the online gaming segment, the only way the developers are able to stay ahead of their rivals is by becoming more inventive in the ‘game features’ department. This is why you will find that the more modern games come with a variety of special features and bonus rounds in order to spice the ‘flavour’ of the game up a bit. Here follows a list of some of several of the more popular features added to games:

  • Free Spins – These can be triggered during base gameplay in many different ways. Basically, this round will allot to you a specified number of spins of the reels without deducting any cash from your bankroll. It’s a free chance at wins. Often, there will be added special features in this round, such extra ‘wild’ symbols or win multipliers to help you along to decent wins.
  • Pick Bonuses – This type of bonus game will often grant you a number of symbols to choose from and a specified number of picks to click on these symbols. Prizes could vary from instant cash prizes to multipliers, to triggers for other bonus games.
  • Bonus Trail – Very similar to the ‘Pick Bonus’, you can click on random items along a trail to reveal prizes or booby traps. Make it to the end of the trail, and you will generally receive a very useful bonus prize.
  • Gamble Feature – Some games providers will add this game as an extra chance to boost smaller wins. After a win (max amount stipulated by the provider in-game rules) you can click on the ‘Gamble Feature’ button to stand a chance of doubling or even quadrupling your last win.

Other Special Features to excite you

There are often other add-on features that keep gameplay alive, that do not necessarily bonus rounds, but help give added value to the bonus rounds. Here is a list of a few of the most sort after features.

  • Wilds – The nature of a wild, is that it will substitute for most standard game symbols to help produce winning combinations. But, there is not only one variation of the wild in the world of online slot games. There are stacked wilds, which come onto the reels in sets of two or more to boost wins; Sticky Wilds, which stay in play without disappearing over a number of wins; Expanding Wilds, which expand to cover a reel’s worth of symbols; and Multiplier Wilds, which will multiply your winnings by a specific amount if it aids in forming a winning combination.
    Often these ‘wild’ types can combine to form more exciting kinds, such as Expanded Sticky Wilds etc.
  • Scatters – These are special icons that do not need to be on a payline to produce a win. Often these symbols will be used as triggers to open bonus rounds. 3 or more scatters on a screen will more often than not trigger a free spin game.

Online Slots hold the greatest variety of titles for your online gambling entertainment, along with some of the best features in the iGaming arena. Head to one of our online casinos to experience a slot adventure to suit you, now!

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