Blockchain as a technology has evolved rapidly, as new techniques deriving from the proliferation of blockchain projects have emerged. Hence the attempts to understand the present day blockchain machinery more closely led to the discovery of bitcoin.

Therefore, in this chapter we will adopt bitcoin as our main example. This choice is due to the fact that bitcoin is the original blockchain implementation, and almost all other projects mimic its design and mechanics.

In the following sections, we will connect to the bitcoin network and store the classic Hello World message into a blockchain. Bitcoin transactions can be used to store small amounts of data in a blockchain—allowing developers to build distributed systems on top of bitcoin, such as Colored Coins, Counterparty, Tierion, and more. 

You would be surprised by the number of hidden messages stored in the bitcoin blockchain.