$BTC The pair $BTC is a vital indicator in the cryptocurrency market, often used to measure the performance of altcoins. Key pairs like $ETH/BTC, $SOL/BTC, and $ADA/BTC reveal how major altcoins are moving relative to Bitcoin. When $ETH/BTC rises, it signals that Ethereum is outperforming Bitcoin. Similarly, $SOL/BTC and $ADA/BTC provide insight into the strength of Solana and Cardano. Monitoring these pairs helps traders spot trends, make strategic entries, and balance portfolios.