$BNB Cryptocurrencies are digital currencies that use cryptography technology to secure transactions and control the creation of new units. The most well-known is Bitcoin, launched in 2009. They operate on decentralized networks called blockchain, which record all transactions transparently and securely. There are thousands of cryptocurrencies, each with unique characteristics. Their popularity has grown due to their potential as an investment and means of exchange, although they also present risks due to their volatility and variable regulation.