Altcoins can be created for a variety of reasons, including to offer improved features or functionality over existing cryptocurrencies, to appeal to a specific niche or community, or simply to capitalize on the growing popularity of cryptocurrencies.
Some popular altcoins include Ripple (XRP), Bitcoin Cash (BCH), Cardano (ADA), and Dogecoin (DOGE). However, there are thousands of altcoins in existence, many of which have little or no real-world adoption or use cases. As with any investment, it is important to conduct thorough research before investing in any particular altcoin.