A blockchain is a “cryptographically secured chain of blocks.” Essentially, this is an interconnected chain of blocks with each containing a hash pointer to the previous block(with the exception of the genesis block), a timestamp, and a transaction record. Each new block is added like a stack on the last block. There are four different types of blockchain; public, private, consortium, and sidechains. Public blockchain networks usually random people to join while maintaining a cloak of anonymity. A public blockchain uses internet-connected computers to validate transactions and achieve consensus. Private blockchain networks use identity to confirm membership and access privileges. Thus only known individuals and organizations can join the network.  The blockchain database once created can be stored using JSON. JSON is a common format that can be read and written easily using Php as a programming language. You can also include an Init method in the chaincode. The init method will serve the initialization function in the chaincode. Usually, this function is never executed. Rather, it will be called in order so as to initialize the chaincode whenever it is started or upgraded.