This document discusses how Bitcoin works through a 7 step process of imagining the creation of a cryptocurrency. It addresses key challenges like removing the need for central trust, preventing double spending, and incentivizing participation. Each step covers techniques like introducing unique identifiers, verifying transactions are not spent before, using proof-of-work to prevent vote buying and allow the first to confirm transactions, maintaining the longest blockchain, and defining consensus on who was first. Drawbacks of the Bitcoin system like performance, data storage needs, traceability, and mining costs are also outlined.