These days, millions of people all over the world are playing different games at online casinos. The best online casinos offer a wide range of games, but the most popular category of casino games are online slots.

Online slots have become one of the most fascinating and fast-moving casino games of all time. They appear by far later than Roulette or Blackjack for example, but since the possibilities are endless with these awesome games, the focus might have twisted a bit.

Some people think that there’s nothing special about slot games - simply press the spin button and see if you’re lucky to land a winning line. But, that doesn’t mean that you cannot benefit from gaining more knowledge about online slots and their features. Whether you’re a newcomer or an experienced slot player, it’s always great to learn something new about these machines.

In this guide, we will be talking about online slots and everything related to them. We’ll tell you how to play these games, how they actually work, and what are the best tips that could increase your chances of winning. After reading our guide, you’ll be ready to start your reel adventure.

In our Beginner’s Guide To Slots, you’ll find

History of Slots

A slot machine, also known as a fruit machine, is a gambling machine with spinning reels. Those reels have symbols on them, which randomly spin after you place your bet. If they line up, you win prizes depending on the value of the symbols.

The first slot machines were known as one-armed bandits because of the large mechanical levers located to the sides. These games have been around since the late 19th century when the car mechanic Charles Fey created the Liberty Bell. 

The Liberty Bell was the first slot machine with three reels. Diamond, spade and heart symbols were included in these reels, along with an image of the Liberty Bell. The original Liberty Bell slot machine can be still seen at the Liberty Belle Saloon & Restaurant in Reno, Nevada.

The demand for the Liberty Bell was huge and Fey wasn’t able to build them fast enough. As a result, more people started building slot machines, including Herbert Mills. He was a manufacturer of arcade machines and he created the Operator Bell, the first slot machine to feature fruit symbols.

In the early 20th century, gambling was illegal in America. That changed in the 1930s when Las Vegas legalised gambling and saved slot machines. It was that time when the popularity of slots started growing. New payout schemes, jackpots, graphic and audio effects, and features were added to these games.

Online casinos were invented during the 1990s with the evolution of computers and the Internet. In 1996, the first online slots started to appear. Since then, the popularity of online slots hasn’t stopped, which has resulted in having a wide variety of online slot games available to play today.

Below we’ll explore how online slots work and what types of online slots you can play. However, make sure to return back to our Beginner’s Guide To Slots as we’ll update it with relevant information as soon as we have it. Online slots continue to develop and bring innovations to the market so we’re excited to see what the next developments will be!

How Slots Work

As we’ve mentioned above, the first slot machines were land-based and located in physical casinos. They required players to insert coins, place bets, and spin the reels. After the spin, you can win a prize, play a bonus round, or not win anything. You can then use more coins and play again.

When it comes to online slots, they work in the same way as land-based slot machines. You still need to insert a certain number of coins (virtual, of course), hit the spin button, and wait for the result. However, they are more advanced and improved, so you might find it difficult to understand how a certain online slot works.

For that reason, here we’ll explain how slots work. And since SlotsWise is all about the best and new online slots on the market, we’ll stick to the online side of these awesome games!

Random Number Generator

Even the simplest online slots are built with a combination of different things that work together to ensure complete randomness and transparency. This means that players can play without worries that they have fewer chances of winning compared to someone else.

At the core of the online slots is the Random Number Generator, also referred to as an RNG. It’s the software with which online slots are built. RNG makes sure that each spin in every online slot has a random outcome. 

Having an RNG into an online slot game allows a unique combination of symbols to land on every spin. For example, if you play an online slot with 5 reels and 3 rows, the number of possible combinations can reach a million. The RNG ensures that all those combinations have the same chance of appearing on every spin, thus creating fair gameplay.

Reels, Rows & Paylines

Simply said, reels are the vertical lines of symbols in a slot game, and they spin around. On the other hand, rows are the horizontal lines of symbols. Both reels and rows can appear in different arrangements but the standard combination in online slots is 5 reels and 3 rows.

Paylines are the winning combinations that form on the reels & rows. They can be horizontal, vertical, diagonal, or in a zigzag shape. If a combination of matching symbols lands on one or more of these paylines, you’ll win. The amount you’ll win depends on the value of the symbols.

In recent years, slot developers have gone way beyond the traditional slot games and they created innovative reels and paylines. For example, we have cascading reels, which give players extra chances of scoring a win on a single spin. 

Or, you must have heard about Megaways, the popular slot mechanic from Big Time Gaming. It allows a different number of paylines to be active on each spin, sometimes up to 117,649. 

Furthermore, there is the Win Both Ways system, which allows you to land winning combinations both from left to right and from right to left. This is included in the mega-popular Starburst slot.

As you can see, the paylines in online slots can be fixed or flexible. Fixed paylines cannot be amended during your gameplay, while the flexible paylines allow you to adjust the number of active paylines on your own.


If you want to land a winning combination when playing online slots, you need to pay attention to the symbols. Symbols are the basis of all online slots. They appear on the reels and rows, creating winning combinations. 

Each online slot has different symbols and different combinations that you can play with. In the Paytable menu, you can see the symbols and how they payout for a certain amount on active paylines.

As soon as you hit the Spin button, the symbols will start to spin and hopefully land in a winning combination.

Here are the most common types of symbols you’ll come across in online slots:

  • Low-value symbols - these symbols give the low-value wins when combined on a spin. Usually, royal symbols like A, K, Q, J, 10 and 9 are used as low-value symbols. Also, you might find games that have card suits as low-value symbols.
  • High-value symbols - these symbols are the ones you need to form combinations with if you want to win big. They reward the biggest prizes in the base gameplay.
  • Scatter symbols - also known as bonus symbols, these symbols are often used to trigger bonus features in an online slot game. The most common role of a scatter symbol is to trigger the Free Spins bonus feature.
  • Wild symbols - these are the most popular special symbols in online slots. The main responsibility of a wild symbol is to substitute for the regular symbols and help you form winning combinations. There are different types of wilds that can appear in online slots, like expanding wilds, sticky wilds, moving wilds, etc.
  • Colossal symbols - as the name suggests, these symbols are huge symbols that can cover several spaces at once. They can land some huge wins, depending on the game’s rules.

Bonus Features

Nowadays, almost every online slot game has bonus features to enhance the gameplay. The bonus features are usually the place where the biggest payouts are awarded to the players. They can be triggered in different ways, depending on the game. The information on how to trigger a certain bonus feature is included in the game’s paytable.

Here are the most common bonus features in online slots:

Free Spins

The Free Spins bonus feature does what it says in the title - it delivers free spins to the player! It’s the most popular bonus feature among slots players. 

This feature is usually triggered when certain symbols appear together on the same spin, such as scatters. The amount of scatters that triggered the feature determines how many free spins you’ll get. 

Depending on the game, you can win from two-three free spins to hundreds in this feature. There are also slots where the number of free spins is unlimited, meaning that you can retrigger the feature as many times as you want, without limits.


Re-spins is a similar feature to Free Spins, as it gives you some form of a free spin. Re-spins are actually a ‘second chance spin’ that can trigger in the base game or as a special bonus feature. The second chance won’t cost you anything, so you’re basically getting a free spin.

Bonus Wheel

The bonus wheel is another popular form of bonus feature in online slots. It works as a built-in mini-game that adds to the overall gaming experience. The wheel is filled with prizes that the player can win. Then, the player spins the wheel, and the pointer lands on one prize, which is awarded to the player.

Pick’em Bonus Game

As its title suggests, the Pick’em Bonus Game presents the player with a couple of things to choose from, each containing a certain reward. Rewards can include free spins, cash prizes, another bonus feature, multipliers, or more. The player needs to choose one of the offered choices and win the reward that hides behind it.


Multipliers in online slots can be in the form of symbols or whole bonus features. When triggered, they will multiply your win by 2, 3, 4, 5, or more times. 

Gamble Feature

Some online slots offer the Gamble Feature after you land a win. You can accept or reject this feature. The Gamble Feature offers players the chance to double their winnings or lose them all.


A jackpot is the highest prize that an online slot offers. There are plenty of jackpot slots available on the market, and they offer different types of jackpots. The most common types of jackpots include local, network, fixed, and progressive jackpots. Some of them are randomly triggered, while others trigger during a bonus feature.

How To Play Slots

As previously mentioned, slots came to this world in the mid-1990s, and they had only three reels and one single payline. Nowadays, you can find slots with more than 100,000 paylines and reels beyond your imagination. Still, the core of the game stays the same - place a bet, hit the spin button, and hope for a winning line.

To help you get the best out of your gameplay, we’ve collected the basic rules on how to play slots online. Consider these key things before you get started with online slots and you’ll have the best gaming experience possible!

Choose the right online casino

Online slots are available to play at online casinos. However, the number of online casinos is huge, so it can be difficult to choose the right one for you. Check our Gude To Online Casinos where we explain what to look for when choosing an online casino to play at. 

And if you don’t want to spend time searching for a casino, you can choose one of the recommended casinos on this page! Rest assured that the casinos we recommend offer a safe, secure, and well-established gaming environment.

Decide the type of online slot you want to play

Now that you’ve found an online casino and have registered and claimed your welcome bonus, it’s time to decide the type of online slot you want to play. There are literally thousands of online slots to choose from, so carefully think about what you want. 

Using the advice in this guide, you can easily find the perfect slot for your needs. And you can always opt-in for the newest online slots on the market that come with innovative features, high-end designs, and huge payouts!

Try playing free slots

There are many online casinos that offer free slots. This means that you won’t be required to make bets, but you won’t be able to win real-money prizes too. Free slots, also known as demo slots, are a great way to test any game you want and see if it's worth playing for real money. Plus, you can have fun without risking your money!

Demo slots have the exact same features as the ones that can be played for real money, which means that you can get familiar with the gameplay, design, symbols, bonus features, RTP, volatility and more.

Set a budget

Before you start playing real-money slots, make sure to set a budget. In that way, you won’t be spending what you cannot afford. Setting a budget will also help you understand how much you want to spend per spin. Online slots offer a wide range of betting options to suit every player’s preferences, so you’ll easily find yours.

Check the paytable

We’ve already explained what the paytable contains and why it’s important, but let’s repeat. The information icon in any slot game will lead you to the paytable. That’s where you’ll find information on the value of the symbols, both low and high-paying. 

The paytable will also show you the paylines, bonus features, maximum payouts, and extra settings. This is important so that you know how to play the slot game and how to form winning combinations.

How To Win In Slots

We’ve mentioned at the beginning of our Guide to Slots that online slots are built with a Random Number Generator that ensures that every winning outcome is randomly generated and transparent. Therefore, there is no ‘magic trick’ that will help you win in slots.
Still, to increase your chances of winning, you have to understand how slots work. This will also help you in making smart gaming decisions and getting the most out of your gameplay.

Every online slot has a paytable that explains symbols, bonus features and winning combinations. Always read the game’s paytable before playing. This will help you understand how to win and how much you can win.

Another key thing that will help you win in slots is the Return to Player (RTP) percentage. RTP is a term used to describe the theoretical payout percentage that is being returned to the player. For example, if you play a game that has a 96% RTP and you put in £100, you can expect to win £96 back, while the rest £4 go to the developer of the slot, the company or whatsoever.

Knowing the game’s variance is also important, as that will help you understand how often you could win. For example, an online slot that pays often has a low variance, and it pays smaller prizes. On the other hand, high variance slots pay less frequent but deliver high-value payouts.

For more details on these specifications, check our detailed Variance, Volatility and RTP Guide.

Remember, online slots involve placing real-money bets. For that reason, you must be careful with your gameplay and place smaller bets, in order to be comfortable with the play. You can also set a betting limit and ensure that you have safe gameplay. Online slots are and should remain a fun activity to spend your free time on, so if you feel at risk when playing, you should stop!

Tips For Playing Slots

To sum up, here are the ultimate tips that will help you have the best experience when playing slots online!

  • Try free slots;
  • Experiment with betting combinations;
  • Place smaller bets;
  • Keep track of your budget;
  • Look into the paytable before playing;
  • Stop playing if you’ve won or lost a substantial amount of cash;
  • Play for fun;
  • Play only at reliable and trusted online casinos!

Best Slot Sites

Online slots are the heart of online casinos. They are easy and fun to play, and some of them offer massive payouts to the luckiest players. The best slot sites have a variety of online slots available to play, with different themes, bonus features, in-game mechanics and jackpots. And we have them on SlotsWise!

Check the featured best slot sites on this page and find the perfect slot for you. With our Beginner’s Guide To Slots, you are ready to start your reel adventure and have fun.

And don’t forget to claim your welcome bonus and win more benefits. From free spins to deposit bonuses, there really is something for everyone!