The digital currency that operates on blockchain technology is Bitcoin, which was introduced in 2009. Bitcoin functions as a decentralized currency, allowing peer-to-peer transactions without the need for intermediaries like banks. Its underlying blockchain technology ensures that transactions are securely recorded and transparent, preventing fraud. This digital currency has paved the way for thousands of other cryptocurrencies, collectively known as altcoins. Cryptocurrencies rely on cryptographic techniques for security, providing users with control over their digital assets while minimizing reliance on traditional financial systems.