Cryptocurrency is a type of digital or virtual currency that uses cryptography for security. It operates on a technology called blockchain, which is a decentralized network that ensures transactions are transparent, secure, and immutable. Unlike traditional currencies, cryptocurrencies are not issued or controlled by any central authority, such as a government or bank, making them independent and often resistant to government interference. Popular examples of cryptocurrencies include Bitcoin, Ethereum, and Litecoin. Cryptocurrencies can be used for transactions, investments, or as a medium for transferring value across borders.