Cryptocurrencies are digital or virtual currencies that use cryptography for security. Unlike traditional money issued by governments, cryptocurrencies operate on a technology called blockchain, which is a decentralized ledger that records all transactions across a network of computers. This makes them secure and transparent, allowing users to send and receive money without the need for banks or intermediaries. One of the most well-known cryptocurrencies is Bitcoin, created in 2009. Since then, thousands of other cryptocurrencies, like Ethereum and Litecoin, have emerged, each with unique features and purposes. People use cryptocurrencies for various reasons, including investment, online purchases, and as a way to transfer money across borders quickly and cheaply.