A blockchain is a growing list of records, called blocks, which are linked using cryptography. Each block contains a cryptographic hash of the previous block, a timestamp, and transaction data. Blockchain has been in a lot of buzz these days. And that is mainly because it is backbone of the very famous cryptocurrency in the world - the Bitcoin. Many Governments and leading Banks have decided to bring many of their conventional transactions based on Blockchain concept. The applications and potential of this framework is huge and is considered to be changing the way transactions are made in various domains. I have been working as a block chain expert for 3 years. Best regards.