Cryptocurrency is a digital or virtual currency that uses cryptography for secure transactions. It operates on decentralized networks like blockchain, making it resistant to government control or interference. Bitcoin, the first cryptocurrency, was introduced in 2009, followed by thousands of others such as Ethereum and Solana. Cryptos allow for peer-to-peer transactions without intermediaries like banks. They are used for various applications including payments, decentralized finance (DeFi), and smart contracts. While offering high potential returns, cryptocurrency investments are also known for volatility, and it's important to research projects thoroughly before investing.