In the previous chapter, we learned how the Ethereum blockchain works and how the PoW consensus protocol keeps it safe. Now it's time to start writing smart contracts as we have have a good grasp of how Ethereum works. There are various languages to write Ethereum smart contracts in, but Solidity is the most popular one. In this chapter, we will learn the Solidity programming language. We will finally build a DApp for proof of existence, integrity, and ownership at given a time, that is, a DApp that can prove that a file was with a particular owner at a specific time.
In this chapter, we'll cover the following topics:
- The layout of Solidity source files
- Understanding Solidity data types
- Special variables and functions of contracts
- Control structures
- Structure and features of contracts
- Compiling and deploying contracts