$BTC

A **coin pair** is a trading duo of two assets on an exchange, shown as BASE/QUOTE (e.g. BTC/USDT or ETH/BTC). The **base currency** (first) is what you’re buying or selling, while the **quote currency** (second) defines its price. Coin pairs fall into three main types: fiat-to-crypto (e.g. BTC/USD), crypto-to-crypto (e.g. ETH/BTC), and stablecoin pairs (e.g. BTC/USDT) . High‑liquidity pairs offer tighter spreads and smoother trades, while low‑liquidity or niche pairs may incur slippage . Understanding pair selection—volume, volatility, fees—is essential for strategic trading and cost‑efficient execution.