Private Keys

It looks like the private key is just a randomly generated set of numbers and letters. The sheer size of the number is what verifies the integrity of key. 10^160 I think it said.

.reddit.com/r/Bitcoin/comments/1jrzr3/what_are_the_chances_of_guessing_a_random_private/

Im gona have a bash at writing a python key generator this weekend.

Yeah it's a massive amount. Most systems now generate a new key for every transaction for security.

Still need to get my head around how keys work but this video from Andreas is probably a good place to start of visit at some point.

https://www.youtube.com/watch?v=PdGRmshPXdo

But it seems the keys can be generated offline and the cryptography can somehow verify that the private key matches with the public. The fact this can't be worked out from someone trying to steal your bitcoin when they have a public key is still a mystery to me, but Andreas helps that understanding a little.