Casinos all over Europe began using single-zero roulette wheels, but when the game made its way to the US, the double-zero was added. This reduced the edge from 5.26% to 2.70%. However, in order to compete, a casino in Bad Homburg, a German casino and spa destination, began offering roulette with only one zero slot for house edge. The wheel was originally designed with 36 numbers and two slots (the zero, and double-zero) that gave the house a small advantage.
In most casinos, two variants exist: American and European Roulette. Nowadays, roulette is enjoyed by millions of people all over the world. In an attempt to create a perpetual motion machine, Blaise Pascal, a French inventor and physicist, inadvertently created a primitive roulette wheel. The very first roulette wheel wasn’t designed for betting purposes.