What's the distinction between a key's fingerprint and the key itself?

Fingerprint is a unique computed fingerprint(SHA-256) key summary of 44 characters and 256 bits which allows you to sign your private key and verify the signature with the public key.

Public/Private keys are cryptographic, hard to forge, symmetric and can be used when you sign a resource key.

Example:

Suppose you have a large PDF document and want a method to ensure we never edit the document. One method to ensure we never edit is to compare your original bit-by-bit document with what we edited to it. This action is known as secure hashing. Calculating numbers is how digital signatures work.

Did you know?

. Bitcoin depends on secure hashing.