An Introduction to Online Casinos

Online casinos are a key part of iGaming industry, and there are thousands of sites to choose from. As a player, it's important to be informed and know how they work before depositing money. It will also help you to make sensible decisions while playing.

How online casinos work

Wikipedia defines online casinos as 'interactive versions of traditional casinos that enable gamblers to play and wager on casino games through the internet' but, to understand how they work, we should go further than this.

Online casinos use sophisticated software – which they normally buy or rent from specialist providers rather than develop in-house – that focuses on three key areas: randomness and fairness, gameplay and graphics, and casino operation. Here's a look at each of these in turn:

  • Randomness and fairness – Some players accuse casinos of being rigged and this is incorrect, as long as you play in a good one. Casino games have an in-built house edge (more on this later), but they are not set up to cheat the player. Instead, the software uses a Random Number Generator (RNG) to ensure that each result is completely down to chance.
  • Gameplay and graphics – Casino software has gone from 2D to 3D graphics in a short time, with VR a growing presence. Its focus on enhanced gameplay also helps this new technology operate smoothly across several platforms, and lets developers add features to enhance the player's experience.
  • Casino operation – The software also helps the casino deal with processes that we don't see on our screens, such as fraud prevention, secure payments, and customer identification and support, so that the player feels safe while playing and the casino keeps everything in order.

Online casinos come in two different forms: on a website or via downloaded software. Web-based or 'instant-play' casinos let you play games directly on your browser, while downloadable casinos require a separate program that you install directly from the internet.

Online casinos vs land-based casinos

The technology that online casinos employ means we can now enjoy great graphics on mobile-friendly sites, use cryptocurrency as our preferred payment method, and benefit from watertight cybersecurity. But are online casinos about to make their land-based equivalents obsolete?

Well, first let's look at what they have in common. Licensed casinos, physical or digital, must follow strict safety standards, whether it be through using Know Your Customer (KYC) and encryption technology, in the case of websites, or being legally obliged to exchange cash for casino chips in the real world.

Yet there are major differences between the two. Whereas you might struggle to think of three bricks-and-mortar casinos in your local area, there is a wide selection of casinos for you to choose from in the comfort of your own home. Finding out how to choose an online casino will help you to have a great playing experience with access to a wide range of games boasting attractive features.

Such variety also means more competition between online casinos, which pushes them to tempt new customers with attractive offers and perks. You might get a free bet at a traditional casino as a welcome offer, but this doesn't compare to the scope of online casino bonuses out there – some offer free spins or credit after each of your first three deposits, while others give you these even without a deposit. Online players can also set game controls, like bet limits, to curb excessive gambling, which land-based casinos don't really have, other than a concerned croupier, perhaps.

Yet, until we have technology that replicates an authentic human experience, online casinos will always lack that essential in-person buzz of a traditional venue. Many players love blackjack and poker because of the thrill of winning against or alongside people they are physically with.

The physical aspect also applies to money: the excitement of winning real cash in a traditional casino is higher than seeing an electronic counter increase online. Also, we can feel the physical money we spend, and this might make use think twice about spending it recklessly. Online betting's lack of 'real feel' is a major contributory factor to problem gambling.

So, while it's true that online casinos provide variety, great perks and game controls, as long as they lack that human touch there'll always be a place for bricks-and-mortar venues.

Also, as a quick side note, there may be key differences between legislation affecting physical and online casinos, depending on the country that you're in. For this reason, it's always a good idea to read up on the local rules before you deposit money in any casino.

A look at online casino bonuses

Bonuses are an important part of the online casino industry, and we can view them from two perspectives.

Firstly, they are a useful perk for a new player – extra credit or free spins are a good way to get to know how an online casino and its games work.

Yet on the flip side, bonuses come with certain restrictions that might make it difficult for the player to get hold of any winnings generated by them.

The two most common bonus types are those that you receive after making a first deposit – the deposit, or welcome bonus, which is added to your funds, and the no deposit bonus, which you get without putting any money down.

These may take the form of extra credit or free spins on certain slots. The casino may also give you a cashback amount, which will be credited to losing bets, or a perk related to its loyalty program.

While these might appear tempting, it's important not to fall into the trap of treating bonuses as 'free money'. Casinos take precautions to make sure players don't indulge in bonus hunting and apply certain rules. It's always important to read the casino's terms to look out for these restrictions, and here are the most common ones:

  • Wagering requirements (WR) – Perhaps the most significant. If you win money with your bonus, you can't withdraw it straight away. Instead, you need to stake a certain amount of money, often many times your bonus amount (x20, for example), to do so.
  • Maximum bet or win – Putting a limit on what you can bet or win helps the casino to control what it gives away.
  • Restricted games – Games with a high RTP are often excluded from bonus use, so take care to only play eligible ones to avoid getting into trouble.
  • Restricted countries – The bonus you can get depends on which country you're playing in.

When it comes to finding casino bonuses, you don't need to check each online casino individually — my list of no deposit bonuses has a selection of free offers for you to browse through.

You'll also see possible bonuses listed in each casino's information box on my list of online casinos, which saves you the hassle of visiting the casino in question and looking for them there.

A summary of gambling mathematics

Online casinos are an entertaining way to pass an hour or two, if used correctly, but, like any other business, they exist to make money. All of their games of chance are set up so that the casino earns a profit in the long term. The house edge, therefore, is the statistical advantage built into games that help them achieve this profit.

The house edge is simply the amount you wager minus a game's return to player ratio (RTP – sometimes referred to as the payout ratio), with the RTP being what you can expect to get back from your wagers over time.


Let's take the example of a slots game that offers a 95% RTP, and so a house edge of 5%. For every $100 that you stake, you can expect to win $95 on average, with the casino taking $5 from you.

However, it's important to remember that this is a long-term average – your actual winnings might be a lot higher in the short term, but they could also be a lot lower. This is where we can take a game's variance, or volatility, into account.

Variance describes how much your bankroll is likely to change while playing a certain game. For games with low variance, small wins are frequent, so it's much less likely for you to stray far away from the long-term value described by the RTP.

However, for those with high variance, your funds are much more likely to fluctuate significantly. While you lose most of the time, there is potential to win big.

While learning about concepts such as the house edge, the RTP and game variance is not a sure-fire way to make money, it does arm you with the wisdom to make better gambling decisions.

To go further on this topic, reading up on how casino games work is a good idea. Most gamblers don't take the time to study these concepts, so by doing so you'll be giving yourself a big advantage — with this knowledge you'll be less likely to fall for some common dangers of casino games, such as trying to win back your losses.

Types of online casino games

Online casino players can choose from a wealth of games to play on, with virtual slots being the most popular, as well as classic casino games, such as roulette, poker and blackjack.

However, these games vary in terms of difficulty, and some may not be suitable for first-time players without reading up on them beforehand. This short guide will give you an idea of what to expect.

Online slots

The easiest game to get into – you simply hit the spin button and see which symbols appear on the reels. This simple concept hasn't changed much since the game was invented well over a century ago, yet most modern slots come with features such as scatter symbols, bonus rounds, free spins, and expanding wilds.

Slots are programmed to have a house edge, but the spins are always random, thanks to the RNG. This makes it impossible to predict what will happen and, although there are certain slots strategies you can employ so that you play in the most effective way possible, even these will not help you make a profit in the long run.

Casino table games

The classic online casino games are the ones that go with a traditional casino setting.

Roulette is, of course, subject to the random drop of a ball, although there are certain probabilities and bet amounts to consider. Video Poker and Blackjack, however, are games that require skill and expert players can use strategies to have a certain amount of control over the game.

Other games

Many online casinos offer alternative games for players to enjoy. Virtual bingo, for example, is a popular choice.

The truth is that there are thousands of games out there for you to choose from, so it's a smart move to try out some of my selection of free casino games to work out which ones are worth spending money on.

Problem gambling and how to gamble safely

The rise of internet gambling presents players with many benefits, but we must also be aware of the drawbacks. Gambling addiction is a big problem and, with people often playing at home alone, it's harder to detect signs of problem gambling.

It's essential that online gamblers view casinos as a form of entertainment, rather than a get-rich-quick scheme or as a way to blow away financial concerns. Reading up on how to gamble safely is essential before depositing real money into online casinos, and knowing how gambling mathematics work is also crucial to keeping yourself safe.

If you, or anyone you know, start to develop signs of problem gambling, then you need to act immediately. Overcoming problem gambling can be a long and painful process, so the sooner you begin the less damaging it will be.

Remember, the safest gambling approach is not to gamble at all but, if you do, then make sure you always gamble responsibly.

Niklas Wirtanen (1)

Niklas Wirtanen

My name is Niklas Wirtanen, I work in the online gambling industry, and I am a professional poker player. Thanks to my years of experience in online casinos and other types of gambling, I've gained a thorough understanding of the ins and outs of this industry, which I decided to share through the Vegas Expert website. I hope my expertise will help make your gambling experience better.

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