$BTC A cryptocurrency trading pair represents two different digital assets that can be exchanged for one another on a trading platform. The pair shows how much of one cryptocurrency is needed to buy a unit of another cryptocurrency. For example, in the pair BTC/ETH, BTC (Bitcoin) is the base currency, and ETH (Ethereum) is the quote currency. This means the pair indicates how many ETH (Ethereum) are required to purchase one BTC (Bitcoin).