TL;DR: Roulette is a casino game where a ball spins around a numbered wheel and lands on a pocket. You bet on where it will land. European roulette has 37 pockets (0–36) and a house edge of 2.7%. American roulette has 38 pockets (0, 00–36) and a higher house edge of 5.26%. Inside bets pay more but win less often; outside bets pay less but hit more frequently. No strategy can guarantee wins, but understanding the rules and managing your bankroll keeps you in control.

How Does a Roulette Wheel Actually Work?

The roulette wheel is the centerpiece of the entire game. At its core, it is a spinning disk divided into numbered, alternating colored pockets. A small white ball is launched in the opposite direction of the wheel's spin and eventually loses momentum, bouncing into one of the numbered pockets. The number and color of that pocket determine which bets win.

Understanding the physical structure of the wheel helps you see why certain bet types exist and how the game is designed to be random.

The Layout of the Wheel

In European roulette, the wheel contains 37 pockets numbered 0 through 36. The zero pocket is green; the remaining 36 are split equally between red and black. The numbers are not arranged in sequential order around the wheel. This is intentional — it ensures that high and low numbers, and red and black pockets, alternate as evenly as possible around the circumference.

In American roulette, the wheel contains 38 pockets: 0, 00, and 1 through 36. The addition of the double-zero pocket is the single biggest rule difference between the two versions, and it has a significant mathematical impact on the player.

The Roulette Table Layout

Alongside the wheel sits the betting table, which is a grid showing all numbers (1–36, plus 0 and 00 where applicable) organized in three columns and twelve rows. Outside this numbered grid are additional betting areas for broader wagers like Red/Black, Odd/Even, and High/Low. Every bet you can make corresponds to a specific section of this layout.

What Are the Different Types of Roulette Bets?

Roulette bets fall into two main families: inside bets and outside bets. Inside bets are placed on specific numbers or small groups of numbers within the main numbered grid. Outside bets cover larger sections of the wheel and appear in the outer areas of the betting table.

Here is a complete breakdown of every standard bet type, its payout, and the probability of winning on a European wheel:

Notice that the three even-money bets (Red/Black, Odd/Even, High/Low) do not actually offer a true 50/50 chance — they sit at 48.65% because zero is neither red nor black, neither odd nor even, neither high nor low. That small gap is where the house edge lives.

What Is the Difference Between European and American Roulette?

This is the most important practical decision you will make as a roulette player. The two versions look nearly identical on the surface, but they carry a meaningful mathematical difference that affects every single spin you play.