Cryptocurrency is a form of digital money that uses cryptography for security and operates on a decentralized system. Bitcoin, introduced in 2009 by an individual or group under the pseudonym Satoshi Nakamoto, is the most well-known example. Bitcoin functions as a peer-to-peer payment system without the need for intermediaries like banks. It relies on blockchain technology, a transparent and immutable digital ledger. While cryptocurrencies offer potential benefits such as faster and cheaper transactions, they also face challenges related to regulation, volatility, and security.