Cryptocurrency is an attempt to create money that does not depend on the trust placed in any state or institution — a motivation that is historically understandable and technically ingenious. Whether the result serves the stated goal better than the systems it proposes to replace is a harder question, and one that requires separating the genuine innovation in distributed ledgers from the speculation and fraud that have attached to them. The technology is real; the claims made on its behalf require scrutiny.
Each step builds on the last.