A BTC coin pair refers to a trading pair where Bitcoin (BTC) is used as the base currency to buy or sell another cryptocurrency. Common pairs include ETH/BTC, XRP/BTC, or ADA/BTC. When trading ETH/BTC, for example, you're buying Ethereum using Bitcoin or selling Ethereum to get Bitcoin. BTC pairs are popular on major exchanges because Bitcoin remains the dominant and most liquid crypto asset. These pairs help traders avoid fiat currency conversions, especially in global markets. Understanding BTC pairs is crucial for advanced trading strategies, arbitrage, and managing exposure to Bitcoin’s price movements.