What is Blockchain? What is Blockchain? Blockchain is a distributed ledger technology. What do I mean by Distributed Ledger Technology? Unlike traditional ways, companies stored data on a centralized location, Blockchain stores data on 1000's of nodes or servers. Even if 1 or 10 nodes go down because of any issue, your applications will still be served by other nodes available on the network which means no government has any control over Bitcoins and no one can shut this down because of its decentralized architecture.