Every node in the Ethereum network holds a copy of the blockchain. We need to make sure that nodes cannot tamper with the blockchain, and we also need a mechanism to check whether a block is valid or not. And also, if we encounter two different valid blockchains, we need to have a way to find out which one to choose.
Ethereum uses the proof-of-work consensus protocol to keep the blockchain tamper-proof. A proof-of-work system involves solving a complex puzzle to create a new block. Solving the puzzle should require a significant amount of computational power thereby making it difficult to create blocks. The process of creating blocks in the proof-of-work system is called mining. Miners are the nodes in the network that mine blocks. All the DApps that use proof-of-work do not implement exactly the same set of algorithms. They may differ in terms of what the puzzle miners need to solve, how difficult the puzzle is, how much time it takes to solve it, and so on. We will learn about...