In 2008 Satoshi Nakamoto introduced the world to the digital currency Bitcoin. This new currency wouldn’t be controlled by anyone, but instead allowed anyone to join their computer hardware in maintaining the system. New bitcoins would be released slowly over time, to those producing new blocks for Bitcoin’s underlying blockchain, as an incentive to support the network. At the same time, Satoshi Nakamoto made it computationally expensive to produce a new block. All machines in the network have to participate in what is effectively a game of “guess the number” where they, through a process of trial an error, try to guess a winning number that will allow them to create a new block and reap the rewards.
Nowadays, the entire Bitcoin network is generating 150 quintillion of such guesses every second of the day non-stop. Even so, the network self-adjusts to ensure a new block will only be generated once every 10 minutes. Since incorrect guesses serve no further purpose, almost all effort produced by the network this way is completely useless. The ultimate goal of this “mining” mechanism is to keep the network secure, as an attacker would have to spend money on hardware and electricity to generate even more useless computations than the ones currently participating, in order to successfully harm the network. In a way, we can compare this to the ghost flights that were observed around the world after COVID first hit in 2020. In order to keep their flight slots, airlines were flying empty planes. Even though this had a purpose, it was a clear waste of resources nonetheless.