Chapter 1

Introduction to Bitcoin

Bitcoin is a digital money system that runs on open network rules instead of a bank's internal ledger. Anyone can verify the supply, send a transaction, or run the software without asking for permission.

That does not make it frictionless or risk-free, but it does make the system unusually transparent. The useful question is not whether Bitcoin is perfect, but what tradeoffs its design makes visible.

Start with the properties that make Bitcoin different from familiar payment systems.

Core properties of Bitcoin

Property	What it means in practice
Fixed supply	Issuance follows code and trends toward 21 million BTC
Permissionless	Anyone can create a wallet and join the network
Censorship resistant	No single operator can easily block valid transfers
Transparent rules	Nodes can inspect and enforce the same public rules

These traits work together: fixed supply shapes monetary policy, permissionless access broadens participation, censorship resistance protects transfer, and transparent rules make the system auditable.

In practice, users experience Bitcoin through wallets, exchanges, and mining headlines. Underneath those interfaces is a simpler idea: shared software deciding which transactions count as valid money movement.

The rest of this course breaks that idea into parts so you can reason about what Bitcoin secures well, where it relies on incentives, and why its design still matters across the broader crypto ecosystem.