The “00” (double zero) in online roulette is specific to the American roulette wheel. The American roulette wheel has 38 pockets: numbers 1 through 36, a single zero (0), and a double zero (00). Double zero increases the house edge, making it higher than European roulette, which only has a single zero. The double zero pocket affects the odds and payouts, making American roulette less favorable for players than European and French variants​.