New Chapter to their textbook free and online, by Tyler Cowen and Alex Tabbarock. They explain cryptography, public and private keys, NFT's and # functions:
Here, for example, is a hash of the entire text of War and Peace: AB8257AE34CE51933B7D6F0B06A486CD1E189636C572B0723A5F 4E341B57A37A
If you are wondering why it’s not a string of 256 0s and 1s, that’s simply because we encoded the same date in a shorter Hexadecimal format. An “A” in this format converts to 1010, for example. Now here is War and Peace hashed but with just one comma missing.
The two hashes look completely different and that is the sense in which a hash produces a digital fingerprint. Another important implication is that a hash function like SHA256 is said to be collision-resistant, meaning that it is infeasible to find two messages with the same hash.