Mining is a key operational concept in understanding how the Bitcoin protocol functions. It refers to a decentralized review process performed on every block of the blockchain to reach consensus, without the need for a central authority to provide trust. In other words, mining is the computational equivalent of peer review in a decentralized environment where neither party involved trusts the other. We will continue our discussion of the hash function here in more depth, as it refers to mining and solving proof-of-work functions. Then, we will integrate the concepts of block target values and network difficulty with mining and how mining has evolved to keep up with the increasing network difficulty. Then, we will discuss the types of hardware designed for mining and analyze the growth of startups that sold dedicated mining hardware. We will then explore how this led to the Bitcoin mining arms race and the startups’ eventual failure. Finally, we will conclude the chapter with a review of hardware advances that are shaping the AI domain.