A BTC coin pair refers to a trading pair that includes Bitcoin (BTC) and another cryptocurrency or fiat currency on an exchange. For example, BTC/USDT means Bitcoin is traded against Tether (USDT), while BTC/ETH represents Bitcoin traded against Ethereum. BTC pairs are crucial in crypto trading, as many altcoins are primarily traded against Bitcoin. These pairs determine the exchange rate between BTC and the paired asset. Traders use BTC pairs for arbitrage, portfolio diversification, and accessing liquidity. Popular BTC trading pairs include BTC/USDT, BTC/USD, BTC/EUR, and BTC/ETH. Liquidity and trading volume vary across exchanges and pairs.