[{"_1":2,"_3":-5,"_4":-5},"loaderData",{"_5":6,"_7":8},"actionData","errors","root",{"_28":-5,"_38":-5,"_39":40,"_41":42,"_43":44,"_45":46,"_47":48,"_49":50,"_51":52,"_53":54,"_55":56,"_57":58},"routes/_store+/_readers+/email_author.$slug/route",{"_9":10,"_11":-5},"book",{"_12":13,"_14":15,"_16":17,"_18":19,"_20":21,"_22":23},"currentUser","id","Z2lkOi8vbGVhbnB1Yi9TdG9yZTo6Qm9va1Byb2R1Y3QvNzk1ODM","title","Twenty One Million","state","published","contactAuthorMethod","email","aboutText","

Everyone has an opinion about Bitcoin. Almost no one can explain it.

A novel you can finish on a long flight — and step off the plane finally understanding how Blockchain actually works.

*Twenty-One Million* fixes that - not with a lecture, but with a story. Four colleagues at a staid insurance company are handed a thankless assignment: decide, in one page, whether the firm should touch Blockchain and Bitcoin. Margaret, who runs risk and trusts no one with money after being burned once, fully intends to write *no*. To do it honestly, she has to understand the thing first -- and so, one Thursday at a time, in the worst conference room in the building, she and three equally skeptical colleagues take Bitcoin apart on a whiteboard and try to break every piece.

They start where everyone's confusion starts (\"what *is* a coin?\") and end up somewhere they never expected: convinced that a ledger no one controls is harder to cheat than the bank down the street. Along the way the book quietly teaches the whole machine - keys and signatures, the chain, mining, why nobody can print more, how to actually buy and hold it without losing everything, and how to spot the scams built to take it from you.

By the last page, you'll actually understand:

What Bitcoin and \"blockchain\" really are -- and why there's no coin anywhere
Keys and signatures, blocks and headers, transactions, nodes, miners and why your money can't be forged or guessed
Mining, and why no one can ever make more than 21 million
How to buy your first bitcoin on an exchange — without getting burned
Wallets, and the twelve ordinary words that hold (or lose) everything
How to spot the scams built to take it from you

It is the rare explainer that respects you enough to be honest about the costs as well as the magic. If you've read three articles about Bitcoin and still couldn't say what it really *is*, start here.

Written by Ritesh Modi - a longtime blockchain educator and author of two books on smart-contract programming - whose philosophy is simple and severe: make a hard thing clear without making it any smaller than the truth allows.

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Kick off your book project, get started with GhostAI, get better at marketing, or spend the day doing all three! Free live workshops on Zoom. Saturday, June 27, 2026.

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