Bitcoin in 10 minutes: the essentials at a glance

Glad you’re here. In ten minutes we’ll lay a solid foundation together – and each section shows you where to dig deeper.

Minutes 1–2: what Bitcoin is

Bitcoin is digital money with no bank, state or company behind it. The idea comes from a nine-page paper published on 31 October 2008 under the pseudonym Satoshi Nakamoto: two people should be able to send each other money directly, without having to trust an intermediary.^[1] On 3 January 2009 the network started with its first block, the genesis blockGlossaryGenesis blockThe very first block of the Bitcoin blockchain, created on 3 January 2009. It contains a newspaper headline about bank bailouts – and its reward of 50 BTC can never be spent, for technical reasons.In the glossary →×.^[2]

‘Bitcoin’ means two things: the network with its rules, and the currency unit BTC. One BTC can be divided into 100 million satoshisGlossarySatoshi (sats)The smallest unit of Bitcoin: 1 satoshi (‘sat’ for short) equals 0.00000001 BTC, so one bitcoin consists of 100 million sats. The unit is named after Bitcoin’s creator, Satoshi Nakamoto.On the learning path: Stage 1 · Step 4 – Sats & units →In the glossary →×, or ‘sats’ for short.^[3] So you don’t have to buy a whole bitcoin: at an example price of $80,000, $50 gets you exactly 62,500 sats (before fees). One bitcoin currently costs $86,292; the sats converter converts your own amounts.

More detail: What is Bitcoin? and The history of Bitcoin.

Minutes 3–5: how Bitcoin works

Imagine a ledger that records every payment ever made. It isn’t kept at a bank: copies of it sit on thousands of computers around the world. That is the blockchainGlossaryBlockchainBitcoin’s public ledger: a chain of blocks in which each block refers to its predecessor. Anyone wanting to change an old entry would have to recreate all the blocks that follow it.On the learning path: Stage 1 · Step 3 – How does Bitcoin work? →In the glossary →×. Three building blocks keep all the copies in sync:

• Keys instead of an account: Owning bitcoin really means owning a secret private keyGlossaryPrivate keyA secret, randomly generated number that you use to sign transactions and so control your bitcoin. Anyone who knows the private key can spend the bitcoin that belongs to it – it must never fall into anyone else’s hands.On the learning path: Stage 5 · Step 3 – Backing up your seed phrase →In the glossary →×. You use it to sign payments digitally.^[1]
• Nodes check: Computers running Bitcoin software, called nodesGlossaryNodeA computer that runs Bitcoin software and exchanges transactions and blocks with other nodes. Together, the nodes form the Bitcoin network; full nodes check every rule themselves.On the learning path: Stage 1 · Step 3 – How does Bitcoin work? →In the glossary →×, verify every payment and every block themselves. Coin Dance counts more than 25,000 publicly reachable nodes (as of September 2026).^[4]
• Miners extend the chain: Miners bundle payments into blocks. To add a block, they have to solve a numerical puzzle that takes a great deal of computing effort: the proof of workGlossaryProof of workThe method by which miners prove that they have done real computing work for a new block. It lets the network agree on the valid chain without a central authority, and makes rewriting old blocks extremely expensive.On the learning path: Stage 1 · Step 3 – How does Bitcoin work? →In the glossary →×. The difficulty adjusts so that a block is created roughly every ten minutes on average. The valid chain is the one with the most computing work behind it.^[1]

This is how a payment works, simplified:

1. Your walletGlossaryWallet (Bitcoin wallet)Software or a device that manages your private keys, generates receiving addresses and signs transactions. The bitcoin itself isn’t in the wallet but on the blockchain – the wallet holds the access to it.On the learning path: Stage 5 · Step 2 – Setting up your first wallet →In the glossary →× creates the payment and signs it with your private key.
2. The nodes check: is the signature genuine? Have these bitcoin not already been spent?
3. Miners include verified payments in their next block. When the network is busy, a higher fee usually gets you in sooner.
4. All nodes add the new block to their copy. Every further block on top makes the payment more secure.^[1]

That’s because every block contains the hashGlossaryHash (hash value)A fixed-length digital fingerprint that a hash function calculates from any data. Even the tiniest change produces a completely different value, and the original data can’t be worked out from the hash.On the learning path: Stage 1 · Step 3 – How does Bitcoin work? →In the glossary →× of its predecessor, a kind of digital fingerprint. Anyone wanting to change an old block would have to redo its computing work and that of all the blocks after it.^[1] Try it – the demo uses real SHA-256; only the puzzle is heavily simplified:

Who decides the rules?

Nobody on their own – not the developers, and not the big miners either. Every node enforces the rules of its own software. Anyone who wants to change them needs broad agreement; otherwise all they get is a separate chain. That is what happened in August 2026 with BIP-110, a proposal intended to temporarily keep data such as images out of transactions: in the two weeks before the split, only 2.53% of blocks signalled support, and the chain its backers split off onto barely moved.^[5] More in Forks & controversies and How does Bitcoin work?.

Minutes 5–6: monetary policy – 21 million and not one more

New bitcoin are created only as a reward for miners. This reward halves every 210,000 blocks, roughly every four years: the halvingGlossaryHalvingEvery 210,000 blocks – roughly every four years – the number of new bitcoin per block is cut in half. The fourth halving, on 20 April 2024, reduced it from 6.25 to 3.125 BTC.On the learning path: Stage 2 · Step 2 – Halving & 21 million →In the glossary →×.^[6] On 20 April 2024, at block 840,000, it fell from 6.25 to 3.125 BTC.^[7] It is currently 3.125 BTC per new block, and the next halving is expected around April 2028.

Because of the continuous halving, the total supply stays just under 21 million BTC; by current calculations, the last fractions will be issued around the year 2140.^[3],[6] So far, 20,093,853 BTC are in circulation, or 95.69% of the final supply – calculated from the current block height and the issuance rules.^[8],[6]

This monetary policy could only be changed if the vast majority voluntarily ran software with different rules. For many people, that is the very core of Bitcoin: nobody can expand the money supply at will. Details: The halving & the 21 million.

Minutes 6–7: why people use Bitcoin – and what critics say

Supporters see Bitcoin as a tool for self-determination; critics see it as a speculative asset with no real use.

We weigh up both sides in Criticism & risks; Energy use & the environment puts the electricity use in context. Why we talk about freedom – and why it means responsibility – is explained in Bitcoin is freedom.

Minutes 7–9: the risks

The price swings sharply. Since 2013, Bitcoin has fallen three times by 77 to 85% from peak to trough. From its record high on 6 October 2025, it fell 53% by 30 June 2026 (all figures in US dollars).^[9],[10] According to our analysis of daily prices since 2013, around three in ten purchases were at a loss one year later.^[9] So far, this volatilityGlossaryVolatilityA measure of how strongly a price fluctuates, usually given as annualised standard deviation in per cent. Bitcoin fluctuates much more than a broad stock index or gold – up and down.On the learning path: Stage 3 · Step 3 – Returns & risk →In the glossary →× has been part of Bitcoin.

A total loss is possible. There is no deposit protection. In theory, bitcoin could become worthless, for example if nobody wanted to buy it any more.^[11]

Mistakes are final. Confirmed payments practically cannot be reversed.^[1] If you lose your private key and recovery phraseGlossarySeed phrase (recovery phrase)A sequence of usually 12 or 24 words from which your wallet derives all its private keys. Anyone who knows the words has full access to your bitcoin – so they belong in an offline backup and never in anyone else’s hands.On the learning path: Stage 5 · Step 3 – Backing up your seed phrase →In the glossary →×, you lose access for good.^[11]

Scammers exploit curiosity. There are platforms where you only appear to buy bitcoin.^[11] Rule of thumb: legitimate providers never ask for your recovery phrase – and neither do we. More in Spotting & avoiding scams.

Tax and regulation are part of it. Gains may be taxable, and in the EU providers are supervised under the MiCA Regulation. Details: Bitcoin & tax in Germany, Bitcoin tax around Europe and MiCA & regulation simply explained.

Minutes 9–10: the right order

You don’t have to buy anything today. The learning path shows the whole way in six stages; Before you start sums up what to know before a first purchase. If you want to buy later, this order makes sense:

1. Check your financial foundations

   Pay off expensive debt and build an emergency fund first – Financial foundations first explains why.

2. Clarify your goal

   Long-term saving, retirement or just understanding for now? The goal compass helps you sort it out, without any investment recommendation.

3. Start small – with an authorised provider

   The criteria are in Choosing the right provider; for an overview, see Providers.

4. Learn about custody

   Before larger amounts build up, you should know who holds the keys: Understanding custody.