The Wheel You See Today Is a Recent Invention
A player walking up to a roulette table today sees a wheel with numbered pockets, a small ball, and a felt layout for bets. That object is the result of several centuries of tinkering, and the version in front of you is not the version someone would have played two hundred years ago. The game's core idea - a spinning wheel and a ball landing in a numbered compartment - has been around in some form since at least the 17th century, but the specific wheel with a single zero, and later a double zero, is a much later development.
The first recognisable ancestor of roulette is generally traced to the French mathematician and philosopher Blaise Pascal, who in the 17th century was working on a perpetual motion machine. He did not succeed at that, but the spinning wheel he built became a foundation for games of chance. By the late 18th century, a game combining a wheel with a betting layout was being played in Paris. The name itself comes from the French word for "little wheel".
What matters for a player is not the exact date of invention but the structural changes that happened along the way. The wheel did not always have a zero. When the zero was added, it changed the mathematics of every bet on the table. When a second zero was added, it changed them again. The history of roulette is largely a history of those two pockets.
How the Modern Layout Took Shape
The roulette wheel as most players know it has 37 pockets on a European layout: the numbers 1 through 36, plus a single zero. The American layout adds a double zero, bringing the total to 38. Those two extra pockets are not decorative. They are the mechanism by which the house edge is built into the game.
In the early Parisian versions of the game, the wheel already had both a single zero and a double zero. The double zero was later removed in European casinos, leaving the 37-pocket wheel that is standard across most of Europe and in many online games. American casinos retained the double zero, and that wheel remains common in the United States and in games marketed as American roulette.
The numbered sequence around the wheel is not random. It is arranged so that high and low numbers, odd and even numbers, and red and black pockets alternate in a specific pattern designed to distribute outcomes evenly around the circle. The arrangement differs between the European and American wheels, but the principle is the same: no section of the wheel should cluster all the high numbers or all the red pockets together.
What Changed When the Zero Arrived
The zero pocket is the single most important feature of the roulette wheel for a player to understand. Without it, a bet on red or black would pay even money, and there would be 18 red and 18 black pockets - a perfectly fair proposition. The zero is neither red nor black. When the ball lands in the zero, a red or black bet loses. That is how the house edge is created.
The same applies to every other even-money bet on the table: odd or even, high or low. The zero sits outside those categories and collects the losing wagers. The double zero does the same thing, which is why the American wheel carries a higher house edge than the European wheel. The extra pocket does not change the payout on any bet; it simply adds one more losing outcome to the wheel.
The table below shows the structural difference between the two main wheel types.
| Feature | European wheel | American wheel |
|---|---|---|
| Number of pockets | 37 | 38 |
| Zero pockets | Single zero | Single zero and double zero |
| Number range | 0-36 | 0-36 plus 00 |
| Effect on even-money bets | Zero loses | Both zeros lose |
| House edge on the same bet | Lower | Higher |
The house edge on a given roulette bet is a fixed property of the wheel, not something that changes from spin to spin. On a European wheel, a bet on a single number pays 35 to 1, but there are 37 pockets, so the true odds are 36 to 1 against. That gap between the payout and the true odds is the house edge. On an American wheel, the same bet pays 35 to 1 against 37 losing pockets, widening the gap.
How a Round Plays Out
Roulette is a comparing game only in the sense that the player's bet is compared against the pocket where the ball lands. There is no opponent hand, no decision about whether to hit or stand. The player's entire strategic input happens before the spin, in choosing which bets to place and how much to stake on each.
A round begins when the dealer, or the software in an online game, opens the betting window. Players place chips on the felt layout, which is marked with the numbers and the various outside betting areas. A player may place multiple bets on the same spin, covering different numbers or combinations. When the betting window closes, the wheel is spun and the ball is released in the opposite direction. The ball loses momentum, drops onto the wheel, and settles in one of the numbered pockets. The dealer marks the winning number, collects losing bets, and pays winning bets according to the posted payout for that bet type.
In a physical casino, players exchange cash for roulette chips at the table. These chips are often a different colour from those used at other tables, so the dealer can tell which player placed which bet. Online, the player selects a chip value from the interface and clicks on the layout to place a bet. The sequence is the same: choose the bet, confirm the stake, watch the spin, and receive any payout automatically.
The Main Bet Types and Their Edges
Roulette bets fall into two broad categories: inside bets and outside bets. Inside bets are placed on specific numbers or small groups of numbers and pay higher amounts because they win less often. Outside bets cover larger groups - red or black, odd or even, high or low, dozens, columns - and pay closer to even money because they win more often.
The important point is that different bets on the same table do not all carry the same house edge. On a European wheel, most bets carry the same edge because the zero pocket affects them all in the same proportion. But some American tables offer a rule called "surrender" or "en prison" on even-money bets, which changes the effective edge on those specific bets. The table below summarises the main bet categories and what they mean for the player.
| Bet type | What it covers | Typical payout | How the zero affects it |
|---|---|---|---|
| Straight up | One number | 35 to 1 | Loses unless the number is zero |
| Split | Two adjacent numbers | 17 to 1 | Loses on zero |
| Street | Three numbers in a row | 11 to 1 | Loses on zero |
| Corner | Four numbers in a block | 8 to 1 | Loses on zero |
| Red or black | 18 pockets of one colour | Even money | Zero loses; some tables offer a partial return |
| Odd or even | 18 pockets | Even money | Zero loses; some tables offer a partial return |
| High or low | 1-18 or 19-36 | Even money | Zero loses; some tables offer a partial return |
| Dozens | 12 numbers | 2 to 1 | Loses on zero |
| Columns | 12 numbers in a column | 2 to 1 | Loses on zero |
None of these bets changes the built-in edge of the wheel. A player can choose bets that win more often or pay more when they hit, but the long-run expected loss is determined by the wheel structure and the rule set, not by the choice of bet. The only exception is when a specific table rule, such as the en prison rule on even-money bets, is in force. That rule returns half the stake or holds it for the next spin when the zero lands, reducing the effective edge on those specific bets only.
Where New Players Go Wrong
The most common procedural mistake at a roulette table is placing a bet after the dealer has called for no more bets. In a physical casino, the dealer announces when the betting window closes, and any chip placed after that moment is returned or moved. Online, the interface simply stops accepting bets. The second mistake is misunderstanding the difference between the two wheel types. A player who has learned the payouts on a European wheel and then sits down at an American table is playing a different game in one important respect: every spin has one extra losing pocket. The third mistake is treating roulette as a game of skill. There is no decision to make after the spin begins, and no strategy chart changes the mathematics of the wheel. The only choices are which bets to place, how much to stake, and when to stop.
Strategy charts do exist for roulette in the form of betting systems, but they are not comparable to the basic-strategy charts used in blackjack. In blackjack, a published chart derives from the specific rule set in use - the number of decks, whether the dealer stands on soft 17, which doubling and splitting rules apply. In roulette, no chart can change the fact that every bet carries a built-in edge. A progression system that doubles a bet after a loss does not remove the edge; it redistributes outcomes into a pattern of small wins and occasional large losses. The wheel does not remember what it did on the previous spin, and no pattern of past results changes the odds on the next one.
FAQ
Is roulette older than blackjack?
Roulette in its modern form is younger than some other casino games, but its wheel-based ancestors go back further than the card games that became blackjack. Blackjack descends from European card games that were formalised in the 18th century, around the same period that roulette was being played in Paris. The two games developed in parallel rather than one clearly preceding the other.
Why does the American wheel have two zeros?
The double zero was part of the early French wheel and was retained when the game spread to the United States. European casinos later removed it, standardising the single-zero wheel. The double zero increases the house edge because it adds one more losing pocket without changing any payout.
Does the age of a roulette wheel affect the odds?
No. A well-maintained wheel, whether new or decades old, has the same number of pockets and the same physical properties. The odds are determined by the number of pockets and the payout schedule, not by the wheel's age. A worn or biased wheel could theoretically produce non-random results, but casinos maintain and test their wheels to prevent that, and online games use a random number generator to simulate a fair wheel.
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