Blockchain infrastructure is a distributed ledger technology that enables secure, transparent, and immutable transactions. It is a decentralized system that allows for the secure storage and transfer of digital assets, such as cryptocurrencies, without the need for a central authority. Blockchain infrastructure is composed of a network of computers that are connected to each other and are constantly verifying and updating the ledger. This ensures that all transactions are secure and immutable, and that no single entity can control the ledger.