The Fibonacci betting system in Roulette is a strategy based on the Fibonacci sequence, where each number is the sum of the two preceding ones. Players start with a base bet and, if they lose, move one step forward in the sequence to determine their next bet. If they win, they move back two steps. The goal is to gradually recoup losses through a series of wins while managing risk. However, this system does not eliminate the house edge, and players can still face significant losses during long losing streaks.