I just read the bitcoin whitepaper front to back. Its only 9 pages, so if you haven't read it yet, do yourself a favor and read it. My takeaways: 1. Bitcoin is a peer to peer CASH system made to transact between people for almost zero fees. 2. Not everyone has to run a full node. SPV makes it so a user only needs to use the headers from the past blocks and only need a partial string of full previous blocks to validate the owners transactions. 3. It was never designed to be priced in FIAT, but to replace it and credit cards.