Back betting involves wagering on a selection to win a particular event, meaning you profit if your chosen outcome occurs, while lay betting is the opposite, where you bet against an outcome, effectively acting as the bookmaker. In back betting, you receive a payout if your selection wins, whereas in lay betting, you pay out if the selection wins, making it a way to benefit from an outcome losing. The two betting types offer distinct strategies and can be used in tandem for more sophisticated betting approaches, such as arbitrage or hedging.