Altcoins—cryptocurrencies developed as alternatives to Bitcoin—have evolved into a diverse and rapidly expanding segment of the digital asset market. While Bitcoin continues to dominate headlines and market capitalization, thousands of altcoins now serve specialized purposes, from enabling decentralized finance to facilitating fast global payments. These assets vary widely in design, risk, and utility, offering both innovation and uncertainty. As the crypto ecosystem matures, altcoins are increasingly shaping its future trajectory.