Blockchain - Despite the inherent ‘Block’ in it, the name has traversed more miles than any other technical term in the recent past. It is echoing in almost all existing IT infrastructures; posing a potential threat to the very existence of the present establishments. The blockchain is said to be the technology of future. Here we are trying to simplify the things for all those who wish to understand the technology. As we indicated in the preface, the book is meant for anyone who wishes to start with blockchain technology.