Triangular arbitrage in the foreign exchange market is probably the most common. It involves exploiting discrepancies in currency exchange rates across three currencies and three exchanges. For example, a trader might exchange currency A for currency B, currency B for currency C, and finally, currency C back to currency A, with the final amount of currency A being more than the initial amount due to rate discrepancies between these transactions.
This strategy takes advantage of inefficiencies in the forex market without needing the underlying currencies to move significantly in value, making it a favoured approach among forex traders for its lower risk profile than other trading strategies.