Launched in June 2000, Betfair is now the world's largest betting exchange. Formed by city traders Andrew Black and Ed Wray, Betfair is based on a stock exchange trader's system, with users able to 'trade' in and out of their positions. The exchange works by customers placing bets with each other either for (back) or against (lay) an outcome. Customers are then charged a % commission on their winnings.
Winning players are not limited Ability to trade any event
Horse racing liquidity is poor early in the day