Cryptocurrency is a digital currency that uses cryptography to secure financial transactions. The first cryptocurrency, Bitcoin, was created in 2009 and introduced decentralized control through blockchain technology. Blockchain uses distributed ledgers to record transactions across multiple computers, making it highly secure. Since Bitcoin, other cryptocurrencies like Ethereum and Litecoin have emerged that enable smart contracts and global payments on open-source, decentralized platforms. While volatile, cryptocurrency trading on exchanges can generate substantial profits for knowledgeable investors willing to take risks.