A free book, published chapter by chapter

Twenty-One Million

Bitcoin, explained with arithmetic instead of opinions. No hype, no price predictions, no jargon left unexplained. Free to read, always — if it earns a tip, the jar is on the front page.

2 of 11 chapters published
  1. The 21 million cap was never voted on or decreed — it's the sum of a geometric series anyone can check with paper and a pencil. Where the number actually comes from, and why it can't quietly be changed.

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  2. What actually changes when a currency's supply is fixed instead of managed — the honest case for both sides, argued fairly, with no verdict forced on you.

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  3. One Hundred Million Satoshissoon

    Why the satoshi, not the bitcoin, is the unit that actually matters once you do the arithmetic on global population.

  4. Blocks: Bitcoin's Clocksoon

    Bitcoin doesn't track time — it tracks blocks. How a ten-minute average becomes the clock the entire schedule runs on.

  5. The Halving Schedulesoon

    Every halving in history, and every halving still to come, laid out on one table.

  6. Why Miners Bothersoon

    The reward keeps shrinking. Why does anyone still spend real electricity chasing it?

  7. Scarcity You Can Auditsoon

    Anyone with a laptop can count every coin ever issued and check it against the schedule. What that actually buys you.

  8. Keys, Custody, and the Only Rule That Matterssoon

    The one rule that outranks every other rule in Bitcoin, and why it can't be delegated to a website — including this one.

  9. UTXOs: Bills, Not Balancessoon

    Bitcoin doesn't have account balances. It has something closer to bills in a wallet — and that changes how transactions actually work.

  10. Lightning: Small Change for a Heavy Coinsoon

    Why a tip jar needs a second layer, and how it keeps Bitcoin's ledger from having to record every cup of coffee.

  11. The Coins That Are Gone Foreversoon

    Millions of bitcoin are provably unspendable. What that does to the real, spendable supply.

New chapters are added regularly. Everything already published stays free. No email list, no signup — just come back, or check the front page.