What the halving changes, and what it does not
The reward for a new block halves every 210,000 blocks. Here is what that means for the network (sample).
Bitcoin, explained in twelve words
Free lessons, evening classes and plain news from Ferrow Bitcoin School (sample) in Springfield. Learn how bitcoin works before anyone tries to sell you anything.
We teach how bitcoin works, not whether to buy it.
The twelve words are the twelve lessons of the course, not a wallet. The amber dot marks lesson 5, the next evening class (sample). Your real recovery words never go on a website, in a photo or in a form.
Before you buy any bitcoin
Bitcoin’s value can rise and fall sharply, and you can lose all the money you put in. Nothing on this site is financial advice: we explain how bitcoin works, never whether to buy it. Payments cannot be reversed, and there is no deposit insurance if a wallet or an exchange fails.
Twelve lessons, in order
Each lesson builds on the one before, from what money is for to how scams work. Read them online for free, or take them as three evening classes.
01 money
What money has to do
Why people agree on money, what makes it hard to fake and who keeps the record of who owns what.
02 ledger
One record, many copies
How thousands of computers keep the same ledger of payments without a bank in the middle.
03 keys
Keys and signatures
A private key signs a payment; the public key lets anyone check the signature without seeing the secret.
04 wallet
What a wallet holds
Wallets hold keys, not coins. Phone, computer and hardware wallets, and what each one protects you from.
05 address
Addresses
Where a payment goes, why a wallet makes a new address each time and how to check one before you send.
06 fee
Fees
What you pay to have a payment included in a block, and why the fee depends on how busy the network is, not on the amount.
07 block
Blocks
A page of payments added about every ten minutes, and why waiting for a few more pages makes a payment final.
08 mining
Mining
How computers compete to add the next block, what that costs in electricity and why it keeps the record honest.
09 halving
The halving
The reward for a new block halves every 210,000 blocks, which is why the total stops just under 21 million.
10 node
Running a node
Checking every rule yourself with free software on an ordinary computer, and what a node can and cannot see.
11 backup
Backups
Writing down recovery words, paper or steel, where to keep them and how to test a backup before you rely on it.
12 scam
Scams
Giveaways, fake support, recovery services and pressure tactics: the tells, and what to do if it happened.
Lessons, evening classes and a workshop
Start online for free, then join the evening course in Springfield library: three Tuesdays, four lessons each, with time for every question.
Online lessons, all twelve
Read at your own pace; each lesson takes about twenty minutes
Free
Evening course, three Tuesdays
18:30 to 20:30 in the library reading room, tea included
$45
Self-custody workshop, Saturday morning
Practise with test coins that have no value
$30
Talk for a library, club or workplace
One hour, up to forty people, questions at the end
Ask us
Example prices. Fees are paid by card or cash at the door; we never take payment in bitcoin.
Bitcoin news, without the hype
Short reports on what changed in the network, the software and the law, and what it means for people who use it. No price calls, ever.
Fake support accounts are answering wallet questions
Ask for help in public and a “support agent” replies within minutes. It is never support (sample notice).
Why fees rose this week: a busy mempool, explained
More payments waiting than space in the next blocks. What it means if you need to send (sample).
Plain answers to the first questions
The six questions asked at every first class, answered in a sentence or two.
What is bitcoin, in one sentence?
Digital money with no company or government in charge: thousands of computers keep the same record of who owns what, and anyone running the free software can check the rules.
Who controls it?
No single person. The rules live in open-source software; changing them needs most of the people who run it to agree, which is slow and rare.
Is bitcoin anonymous?
No. Every payment is on a public record. Addresses carry no names, but they can often be linked to people, for example through the exchange where coins were bought.
Why do fees change?
Each block has limited space. When many people want to send at once, they offer higher fees to be included sooner; when the network is quiet, fees fall.
Should I buy bitcoin?
We cannot answer that for you and we will not try. Bitcoin’s value can rise and fall sharply, and you can lose all the money you put in. Nothing on this site is financial advice: we explain how bitcoin works, never whether to buy it.
What do I need for the course?
Only curiosity. You do not need to own bitcoin, open an account or install anything for lessons 1 to 10.
Three rules we repeat in every class
Your recovery words are yours alone
Nobody genuine will ever ask for them: not support, not a teacher, not a wallet app. Anyone who has the words can take everything.
Nobody can double your coins
Giveaways, mining clubs and investment groups that promise returns are scams, however real the website looks.
Support never messages you first
Fake helpers answer public questions within minutes. Contact a company only through its own app or website.
Asked to pay in bitcoin? Stop.
A fine, a tax, a parcel fee or a “fix” for your bank account paid in bitcoin is a scam every time. Hang up, close the chat and talk to someone you trust.
Bitcoin’s value can rise and fall sharply, and you can lose all the money you put in. Nothing on this site is financial advice: we explain how bitcoin works, never whether to buy it.
Self-custody workshop, with test coins
On Saturday mornings we set up a wallet together using testnet coins, which have no value, so a mistake costs nothing. You write the recovery words on paper, wipe the wallet, restore it from the words and send a test payment to your neighbour.
- A charged laptop or phone, and a pen
- No bitcoin, no exchange account, no card details
- Two hours, twelve seats, two teachers
Holding your own keys means nobody can reverse a mistake or recover lost words for you. Bitcoin’s value can rise and fall sharply, and you can lose all the money you put in. Nothing on this site is financial advice: we explain how bitcoin works, never whether to buy it.
Start with lesson 1 tonight
Lesson 1 takes twenty minutes online and costs nothing. When you are ready, book a seat at the evening course.