Altcoins are cryptocurrencies other than Bitcoin. The term "altcoin" combines "alternative" and "coin," indicating that these digital currencies serve as alternatives to Bitcoin. They can vary widely in purpose, technology, and market value, with some aiming to improve upon Bitcoin's features or address specific issues within the cryptocurrency space. There are thousands of altcoins available, including well-known examples like Ethereum, Ripple, and Litecoin. Each altcoin may offer unique functionalities, such as smart contracts or faster transaction times. Investors often explore altcoins for diversification or potential growth opportunities beyond Bitcoin's established market presence.