“So what is a Bitcoin and what is this blockchain thing that it runs on?”
If you’ve spent any significant time working with, investing in, or even just following the cryptocurrency and blockchain industry, you’ve been asked this question. Generally by people who also ask you to help them change the wallpaper on their iPhone.
You’ve probably got a quick spiel down, but you also probably get into the weeds very quickly when you try to get past, “it’s a ledger that can’t be changed.” That’s particularly true when talking to the technophobic or the scientifically disinclined.
There’s an easier way. Just forward them a link to this interview with former NSA analyst Edward Snowden. Whether they consider him a heroic whistleblower and champion of personal privacy or a traitor who did immense damage to his country, no one denies that Snowden is very, very smart.
He is also, according to attorney Ben Wizner, director of the ACLU Speech, Privacy and Technology Project, “the clearest, most patient, and least condescending explainer of technology I’ve ever met.”
In this November 2018 interview with Wizner, originally published in McSweeny’s, Snowden starts by answering, “What the hell is a blockchain?” From there he ranges through, “Why is a ‘bitcoin’ worth anything” and “Hashing is a real verb?”
At no time does he use a single word the average non-techy wouldn’t understand.
By way of example, here’s how Snowden uses the example of that most ubiquitous of internet memes, the cat picture, to explain hashing:
BW: “Hashing” is a real verb?
ES: A cryptographic hash function is basically just a math problem that transforms any data you throw at it in a predictable way. Any time you feed a hash function a particular cat picture, you will always, always get the same number as the result. We call that result the “hash” of that picture, and feeding the cat picture into that math problem “hashing” the picture. The key concept to understand is that if you give the very same hash function a slightly different cat picture, or the same cat picture with even the tiniest modification, you will get a WILDLY different number (“hash”) as the result.
BW: And you can throw any kind of data into a hash function? You can hash a blog post or a financial transaction or Moby-Dick?
ES: Right. So we hash these different blocks, which, if you recall, are just glorified database updates regarding financial transactions, web links, medical records, or whatever. Each new block added to the chain is identified and validated by its hash, which was produced from data that intentionally includes the hash of the block before it. This unbroken chain leads all the way back to the very first block.
Think you can do better?