notes:

learning about bitcoin. reading the protocol, I see that "double-SHA-256" is used.. what does that mean? they give an example, of double hashing "hello".. ahh, I can reproduce what they're showing with:

console.log(require('crypto').createHash('sha256').update('hello').digest('hex'))

console.log(require('crypto').createHash('sha256').update(require('crypto').createHash('sha256').update('hello').digest('binary')).digest('hex'))

..note that the second line has a digest('binary') in there instead of a digest('hex').

..hm.. bitcoin uses elliptic curve public-key cryptography.. reading a bit about that.. I don't understand it yet, but I think I'm going to bed..