In cryptocurrency and traditional finance, a trading pair is a market between two assets, like BTC/ETH or USD/EUR. It shows how much of one asset (the quote currency) is needed to buy one unit of the other (the base currency). For example, in the BTC/USD pair, Bitcoin is the base, and USD is the quote. If BTC/USD = 50,000, one Bitcoin costs $50,000. Traders use pairs to switch between currencies or assets without converting to fiat. Understanding trading pairs is crucial for navigating exchanges, spotting arbitrage opportunities, and managing portfolio risk. Always check liquidity and fees before trading.