BTC
for Starters
Forget the price charts. The real revolution is architectural. A breakdown of the protocol that enforces truth without authority — and how you can participate today.
Start LearningWhat is Bitcoin?
Forget everything you know about money for a moment. Imagine you were handed the task of inventing it — not in the 12th century, but today. What would you actually build?
Reinventing Money From Scratch
If you were designing a way for people to exchange value today — with modern technology at your fingertips — would you really land on metal coins and paper slips? Probably not. There has to be a better way. What if instead of handing someone a physical thing, you just wrote it down?
Keep a Shared Ledger of Value
Start simple: keep an electronic ledger that records how much value each person holds. If you do some work for me, I transfer some of my value to you. The ledger is updated. No cash changes hands. No bank required. We just need everyone to agree that the ledger is the truth.
We'll call this unit of value a Bitcoin.
Addresses Instead of Names
The ledger needs to know who owns what — but we don't want real names attached. So each participant gets a unique identifier called an address. The ledger tracks how much value each address holds. Your address is your identity on the network, and the software that manages your addresses is called a wallet.
The Blockchain
This ledger — the complete record of every Bitcoin transaction, from the very first one in 2009 to the one happening right now — is called the blockchain. It is public, permanent, and ordered in time. Nothing can be deleted. Nothing can be quietly changed. It is the single source of truth for who owns what.
Spread the Ledger Everywhere
Here's the critical question: who makes sure nobody lies about their balance? If one person controls the ledger, they can cheat. The solution is elegant — give an identical copy of the ledger to tens of thousands of computers worldwide. When someone wants to spend Bitcoin, the whole network checks whether their story matches what everyone else already knows. If it doesn't add up, the transaction is rejected.
Why Would Anyone Run This?
Maintaining a copy of the ledger and verifying every transaction takes real computing power and electricity. So why would anyone do it? Because they get paid. Participants who do this verification work — checking transactions, grouping them into blocks, and securing the history — are rewarded with newly created Bitcoin. These participants are called miners.
Miners are also competing against each other to be the one who adds the next block, which means any miner who tries to cheat would be immediately caught and lose their reward. The financial incentive keeps everyone honest.
You Just Invented Bitcoin
A shared electronic ledger, maintained by tens of thousands of independent computers, where value is tracked by address, transactions are verified by consensus, and participants are rewarded for their honesty. No government prints it. No bank controls it. No company owns it. The rules are enforced by math and code — the same for everyone, everywhere, at all times.
That is Bitcoin. A digital, decentralized currency — and the first time in history that digital scarcity has been solved without a trusted authority in the middle.
Blockchain
The public ledger recording every transaction since 2009 — permanent and tamper-proof.
Wallet & Address
Your unique identifier on the network. Your wallet manages your addresses and keys.
Decentralized
No single point of control. Tens of thousands of nodes each hold a full copy of the ledger.
Miners
Participants who verify transactions and secure the ledger — paid in Bitcoin for honest work.
Trustless
You don't trust a bank or company. You trust open-source code and cryptographic math.
The Core Stack
Three layers of technology working in unison to create a decentralized network anyone can join. Click any layer to go deeper.
Digital Keys
How secret codes and math prove you own money without showing who you are.
The Blockchain
A digital history book that is impossible to tear pages out of or rewrite.
The Network
Why nobody is in charge, and why that makes the system stronger than a bank.
Your Wallet
It doesn't hold coins — it holds keys. How to set one up safely.
See It Happen
A faucet drips small amounts of simulated Bitcoin to help you experience real peer-to-peer transactions — without spending a cent.
💡 This simulator is a sandbox — no real network, no real fees, no real confirmations, and the balances reset every time you refresh. Want the real thing? Bitcoin: Under the Hood, the full course, walks you through sending an actual test-network transaction and mining a real SHA-256 hash by hand. See what's in the course ↓
Bitcoin: Under the Hood
You've got the concepts. This is the part where you actually use them — buying, securing, verifying, and spending real Bitcoin, with the mistakes people make laid out before you make them.
Isn't this just the free site again?
No. Everything you've read so far is the foundation — what Bitcoin is and why it works. The course is the practice: how to actually buy your first Bitcoin without overpaying, move it into a wallet you control, read any transaction on a block explorer, set a fee that doesn't get you stuck, and recognize the scams that have cost real people real money. Module 0 is a fast recap of what's here, so nothing is repeated at length — it's a bridge, not a rerun.
🎯 What you'll be able to do
- Buy your first Bitcoin without getting quietly charged 3–4% in hidden spread
- Move it off the exchange into a wallet only you control — and verify it arrived
- Read any transaction or block on an explorer and understand every field
- Pick a fee that confirms when you need it to, and rescue one that's stuck
- Back up a seed phrase so a house fire or a lost device isn't a total loss
- Spot the eleven scam patterns that account for most real-world losses
- Send money abroad in seconds over Lightning instead of days over wire
- Keep records that won't leave you guessing at tax time
📚 What's inside
- 00Foundations Recap — the four core ideas, condensed
- 0.5Your First Bitcoin — exchanges, fees, first withdrawal
- 0.7How Money Broke — the cypherpunks, Satoshi, the whitepaper
- 0.8Hands On — explorer labs, test transactions, mine a hash
- 01The Mempool & Fees — why it's stuck, how to fix it
- 02Block Explorers — verify everything yourself
- 03Security & Self-Custody — wallets, backups, inheritance
- 04Living With Bitcoin — receiving, taxes, scams, Lightning
- 05Everyday Use & Earning — real spending, honest income paths
- +Case studies & reference — FTX, the landfill hard drive, glossary, topic index
How it's delivered
The course lives in Notion. You get a link, click Duplicate, and the whole thing copies into your own Notion account — yours to keep, permanently, even if you never pay for anything else. Tick off the checkboxes as you go and your progress saves automatically across every device. A free Notion account is all you need, and there's no subscription, no login to a course platform, and no access that expires.
Or send a note below and I'll email you when it's live.
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