A coin pair in crypto trading, like PR/USDT, represents the exchange rate between two assets—PR (a crypto token) and USDT (a stablecoin). It shows how much USDT is needed to buy one PR token. Traders use coin pairs to speculate on price movements, swap between currencies, and manage portfolio value. The first currency is the base, and the second is the quote currency. High-volume pairs offer better liquidity and tighter spreads. Pairs may involve fiat, stablecoins, or crypto-to-crypto. Always research a token’s background, project goal, and market trends before trading, as prices can be highly volatile and unpredictable.