By taking a walk in my oldest threads, I wondered what part of Bitcoin was the most difficult, for me, to grasp. I think that I'm between the “Miners have a stronger voice than the rest of the users consensus-wise” argument and the block-size debate.
Right next to those, I'll easily put Elliptic Curve Cryptography and the Lightning Network as a concept. How about you?
Actually a lot. mostly about the technical things and the whole blockchain system and how is it built to create a peer to peer transaction system.
Till today i just used bitcoin to do the transaction and earn money from it but don't find out about it yet, later i will learn about the blockchain programming to learn about the fundamental how the system works.