Coin pairs represent the trading relationship between two cryptocurrencies on an exchange. One coin is quoted against another, like BTC/ETH, showing how much of the second coin (ETH) is needed to buy one unit of the first (BTC). Bitcoin (BTC) is often used as a base currency in many trading pairs due to its liquidity and dominance. For example, BTC/USDT shows how many Tether (USDT) are needed for one BTC. Understanding pairs helps traders analyze market trends, arbitrage opportunities, and price movements. Trading strategies often rely on the dynamics between coin pairs and Bi$BTC