What is the house edge? In simple terms, edge refers to the advantage one person has over another.

For example, if you played tennis against Andy Murray, he would have the edge over you. The same idea applies to online casino games, but the meaning is a little more complex.

To understand the house edge, you first need to know about odds.

Every bet you make in a casino has a mathematically determined outcome. For example, if you flip a coin, there are two possible outcomes: heads or tails.

Based on this, you have a 50 per cent chance of making the right prediction.

The same rule applies to casino games. On a European roulette board, there are 37 numbers and if you bet on a single number, you have a 1 in 37 or 2.7 per cent chance of being correct.

Whenever you play, these odds remain the same.

But casinos are businesses and there wouldn’t be a profit in it if the true odds determined a game’s prize structure.

To counter this, the payout odds will deviate slightly from the true odds. For roulette, this means the returns on a single number win are 35 to one (i.e. one in 35).

Expressed as a percentage, the odds a single number should be 2.63 per cent as opposed to 2.7 per cent. This small difference between the true odds and the payout odds is what determines the house edge.

How do different casino games have different odds?

The interesting thing about odds is that they can change. Casinos have the power to tweak their payouts any way they like.

This opens up some interesting possibilities.

Firstly, it means different games have a different house edge. Secondly, different casinos can have different payout odds.

In practice, the latter is less common, but every popular casino game will hold a different house edge. As a player, you can choose the best spots to put your money in.

Looking at different casino games, the most popular games are:

- Video slots

- Blackjack

- European roulette

Although video slots are programmed differently, the average edge for these games is between two per cent and 10 per cent.

For blackjack, you’ll typically face a seven per cent edge.

Finally, European roulette, the house edge is 2.7 per cent. Looking beyond the top games, the lowest house edge casino games are:

- Caribbean stud poker = five per cent edge (on average)

- Pai gow poker = 2.6 per cent edge (on average)

- Video poker = 0.5 per cent to five per cent edge (on average)

- Three card poker = 1.5 per cent edge (on average)

- Baccarat = 1.5 per cent edge (on average)

- Craps = 1.4 per cent to five per cent edge (on average)

How to apply house edge to casino games

Just as the casinos have the power to work the odds in their favour, you have a similar ability. For each game you play, there are mathematically correct moves and mathematically incorrect moves.

What’s more, there are higher risk bets than others. To the second point, roulette is a great example.

Although the house edge won’t change, you can reduce the impact it has. For example, if you bet £1 on red, you’re almost 50/50 to win. In contrast, if you bet on the number 27, you’re a 37 to one shot.

For those that don’t want to be exposed to as much risk, the outside bets are a great way to work with the odds. This doesn’t mean you can turn things in your favour, but you can make bets where you have a better chance of winning.

Beyond choosing the right bets, you can learn betting strategies.

Blackjack is a game that’s commonly open to this sort of play. Based on something known as mathematical expectation, expert players know when it’s correct to stand, hit, double down and split.

This expectation is based on mathematical analysis and refers to the overall outcome.

In other words, if you made XX move 1,000 times, you the mathematics suggest you would end up in profit. In practice, the move may result in a loss. However, if you stick at it, you would theoretically be a long-term winner.

Moving forward with the knowledge of house edge

Anyone that can learn the correct plays has a shot at reducing the house edge.

This is only true for casino games with an element of skill involved  (i.e. you can’t really have a strategy for slots).

It’s important to note that it won’t guarantee you a profit but, as we’ve said, the house edge is simply based on a set of numbers that can be tweaked.