Number Go Up: Inside Crypto's Wild Rise and Staggering Fall

by Zeke Faux

The problem was that someone could try to spend the same Bitcoins twice at the same time—more or less cutting and pasting money. The solution that Bitcoin uses to prevent this “double-spending problem” is called “mining,” and it’s incredibly complicated and confusing. It also uses so much electricity that the White House has warned it might prevent the United States from slowing climate change. It’s like something out of the world’s most boring dystopian science-fiction movie. I will attempt to explain. Here goes: Once enough messages about transactions come in, some computers in the network called miners compile the batch into what’s known as a “block.” They confirm that I actually have 1,000 Bitcoins and that I haven’t already sent them to someone else. Then they make the block official and add it to the existing list of blocks—the blockchain. But these miners don’t just hold a vote on whether the transactions are valid. That would require trusting a vote-counting system. Instead, the miners have to compete in an impossibly hard guessing game to generate a random number—as of 2023, the odds were 75 sextillion-to-1 against a correct guess. The winning miner gets to publish the block and update the ledger, and they get a reward of six and a quarter brand-new Bitcoins, created out of the ether automatically. The difficulty of the game automatically increases when more miners enter it.