$BTC

A BTC coin pair represents the exchange rate between Bitcoin (BTC) and another asset, which can be another cryptocurrency or a fiat currency. It's displayed as "BTC/X," where X is the other asset.

For example:

* BTC/USDT: Shows how much one Bitcoin is worth in Tether (a stablecoin pegged to the US Dollar). This is one of the most common and liquid pairs.

* BTC/USD: Indicates Bitcoin's price in US Dollars.

* BTC/ETH: Represents how much Ethereum (ETH) you can get for one Bitcoin.

These pairs are fundamental for trading, allowing users to buy or sell Bitcoin for other assets and enabling speculation on their relative price movements. Bitcoin's widespread adoption makes it a common "base currency" against which many altcoins are traded.