BTC was not the first cryptocurrency!! I'm not just putting in my exclamation points out of excitement, I'm basically shouting this all the time. It doesn't take away from Nakamoto's (and Finney's, and other's) technical step forward to point out that it's basically an innovative way to combine a TON of important prior work. I shout this from my car at stoplights to get across the idea that there's a lot of ways to build a digital currency, and cryptos are neither the only way to do it, nor the best for most purposes.

A big one (that I'm a big fan of) was David Chaum's DigiCash from the '90s -- it was arguably more about the cryptographic tech than "cryptos" are today. Super intelligent and interesting, a way to make a perfectly private digital version of physical cash. Google his name and you'll find all his papers. It almost took off, too -- the internet we know now would be way, way different if it had. And better, I think.

Likewise, a lot of the people who ended up helping out with BTC in one way or another made earlier versions. Hal Finney made "RPOW," these very clever digital tokens; Nick Szabo made a bunch of experiments with "bit gold" and ideas for using digital signatures; Adam Back cooked up a fantastic tool called "hashcash" with a lot of applications.