The game is designed to be random, and the odds of each number or color coming up are the same on every spin. There is no strategy or pattern that can reliably predict the outcome of a roulette spin.
The wheel spin in online roulette is simulated by a Random Number Generator, or RNG. The RNG uses a number from a previously set feed of seed numbers and an algorithm to produce a number from 0-36 as randomly as possible.