The technology utilized for creating digital currencies is blockchain. Blockchain is a decentralized digital ledger that securely records all transactions across a network of computers. It ensures transparency, security, and immutability, making it a foundational technology for cryptocurrencies like Bitcoin and Ethereum. Each block in the chain contains a set of transactions and is linked to the previous one, preventing alteration or tampering. This technology not only underpins digital currencies but is also being explored in various sectors for applications like supply chain management and smart contracts.