However, this is one of only a few similarities between the wheels used in European roulette and American roulette.
The most well-known and understood difference between the pair is in the quantity of numbers present on the wheel – with the American wheel having 38 to Europe’s 37.
Both hold every number between 1 and 36, alternating between red and black. The number one is red on both, two black etc. Then each have a green zero.
Where the difference lies is that the American wheel has an additional green 00, which is effectively only used to bolster the house edge of a casino.
Much lesser known is the running order of the numbers around the wheel.
Players will be familiar that the numbers do not run in any decipherable sequence, which is a strategy clearly adopted to mystify rookie players and make it more difficult to identify any winning patterns which may be emerging.
For example, on an American wheel if three successive winning numbers were 16, 4 and 23, most players would fail to notice that these numbers are positioned next to each other. Such knowledge would be highly valuable ahead of the following wheel spin.
But, the random chain of numbers differs on European wheels, even though the principle of avoiding having two red or two black numbers side by side remains.
In theory, roulette should be a balanced game. Not only do the colours alternate, but around the majority of the wheel odd and even numbers do too.
What this does is prevents the creation of sections of the boards which considerably favour those who place what are referred to as even bets. Beginners to the game may start by opting for either red or black or odd or even.
The excitement in roulette is watching the ball bounce around into the small segments before settling into the winning number. If four odd numbers were positioned next to each other, some of the enjoyment would be removed as it could be predicted while a spin is still in progress whether there was a strong possibility that it would come to rest in this section.
This is the number sequence on a European wheel:
Alongside the even bets, other wagering opportunities on the outside of the roulette layout are in the dozen sections. Players can bet that the winning number falls between 1-12, 13-24 or 25-36.
However, betting on the second of these sections could be considered especially dangerous. Look at the nine-number section of the wheel between 29 and 32 and what can be interpreted?
None of these numbers fit into the 13-24 section, meaning if a ball has a run of falling into this area, putting chips on this winning dozen would be foolish.
Alternatively, if it is determined that the ball is rarely landing in this region, it could make sense to only bet on the second dozen as the chances of being a winner would be much greater than one in three.
Another even bet in roulette is high or low – whether the winning number will be between 1-18 or 19-36.
There is only one section of the European wheel where two numbers are adjoined from the same high or low section and that is the red 5 alongside the black 10.
This is the layout of the American wheel:
It is far less balanced in the sense that two high or low numbers next to each other is far more common. For example, 26 is next to 30, 21 is beside 33, and 29 and 25 are side by side.
But there seems little advantage to be gained, given that the spread of low and high numbers being positioned together is similar.
Where the balance is better on the American wheel is in opposites. If standing directly in front of one number and looking across the wheel, a person will see another number one to the side of that ahead of them.
So stand in front of 11 and opposite is 12, while facing 23 is 24.