Blockchain is a database of records, which tracks Querythe history of all transactions and communications between different nodes of a network. It provides a decentralized platform to execute transactions with mutual trust among the participants, while at the same time, eliminating the presence of a central mediating authority. Record of every transaction is stored in the Blockchain and is entirely tamper-proof. Blockchain creates a peer-to-peer network where all nodes get to verify transactions occurring in the network, through a consensus-based governance system. It has been used to implement the world's most popular cryptocurrency Bitcoin. This is a highly promised technology, which is being adopted and implemented in several domains, such as Internet-of-Things-based systems, health care, energy systems, education systems, banking, and many more.
Bhadoria, R. S., Nimbalkar, A., & Saxena, N. (2020). On the Role of Blockchain Technology in the Internet of Things (pp. 129–140). https://doi.org/10.1007/978-981-13-8775-3_6