736 THE CONNECTED BITCOIN ATLAS
Understand one idea.
Follow the whole system.
Every entry is a coordinate, not an island. Move from the monetary rule to the code that enforces it, the people who shaped it and the trade-offs it creates.
Atlas
736 verified coordinatesBrowse the complete Atlas directory
Bitcoin
Digital money without a central operator: a network in which anyone can transfer value and independently verify that the same rules apply to everyone.
Satoshi Nakamoto
A name without a verified face, under which the Bitcoin Whitepaper, the first software and a network that kept running after its author left came into being.
Bitcoin Whitepaper
Nine pages about sending digital money without a bank in between. A guide to the original proposal and what it does not contain.
Genesis Block
Bitcoin began with a block carrying a newspaper headline, before there was an exchange to trade on. The Genesis Block of January 3, 2009 gave the network a shared starting point. Its story separates verifiable data from interpretation and…
Timechain / Blockchain
Bitcoin's shared block history: it determines which payments were confirmed and in what order, without a single central authority keeping the record.
Proof of Work
The mechanism by which Bitcoin turns electricity and computing power into an easily verified proof, then uses accumulated work to order valid block history.
Mining
How pending payments become a confirmed block, what miners get paid for, and why everyone else still needs to check their work.
Full Node
Checking Bitcoin payments and blocks yourself: what a node verifies, how a wallet uses it, and why you need neither mine nor keep every block forever.
Difficulty Adjustment
How Bitcoin adjusts the effort required to mine, keeping the long-term average close to one new block every ten minutes.
Transaction
What happens when you send bitcoin: where the amount comes from, where the change goes, and when the payment is confirmed.
UTXO
An individual unspent amount in Bitcoin. Why your balance can contain several of them, and what that means for payments and fees.
Private Key
The secret a wallet uses to authorize payments. How private keys work, why they must stay private, and how they differ from a PIN and recovery words.
Wallet
How to receive and send bitcoin, who holds the keys, and what you will need if you lose your phone or signing device.
Block Subsidy
The part of a block reward made up of newly created bitcoin. How it differs from fees, who enforces the limit and why it gradually falls.
Halving
Why fewer bitcoins are created in each successive period, what this means for miners, and why a halving does not cut your savings in half.
21 Million
Why today’s rules prevent an endless supply of bitcoin, who checks them, and what the limit means for holders.
Mempool
Where a payment goes after you send it, why it sometimes waits, and why disappearing from an explorer does not mean it has been cancelled.
Transaction Fees
Why a small payment can cost more than a large one, who receives the fee, and what you can do when a transaction is waiting.
SegWit
A change that makes it easier to build on Bitcoin transactions and counts their signature data less heavily towards block capacity.
Taproot
A Bitcoin improvement that lets key holders spend by agreement and reveal alternative rules only when they use them.
Lightning Network
How to pay with bitcoin without recording each payment in a block, why channel capacity matters, and what safe self-custody requires.
Block
A block groups selected transactions into one record linked to earlier history and independently checked by every full node.
Block Header
The small part of a block that ties its contents to earlier history and allows mining work to be checked.
Hash
A short digital fingerprint that helps compare data and detect changes.
SHA-256
A short fingerprint can represent text, a file or a Bitcoin block header. How does it help detect changes, what are miners looking for, and why is hashing different from encryption?
Merkle Tree
A way to summarize transactions with one fingerprint and verify a payment’s inclusion without downloading the whole block.
Bitcoin address
You give someone an address from your wallet when they want to pay you in bitcoin. How do you use it safely, why does it change for the next payment, and what can it really tell you about the recipient?
Seed Phrase
Why a wallet shows you a list of words, what they can restore after you lose your phone, and how to keep them from helping a thief too.
BIP 39
Recovery words are meant to let you regain access to a wallet when the original device stops working. BIP39 explains how those words are created and how a compatible wallet uses them to recover the starting material for its keys. Recovery…
HD Wallet
A wallet can offer a fresh address for each payment without requiring a new key backup after every receipt. An HD Wallet derives a whole tree of keys from one starting secret. Recovery also requires knowing which part of the tree the wallet…
Multisig
A payment need not depend on a single key. Multisig can require, for example, any two of three independent keys to sign.
Cold Storage
Bitcoin is not stored in a safe or on a USB drive. The network records the coins; what we protect are the keys that let us spend them. Cold Storage separates those keys from an ordinary online computer. Long-term protection also requires a…
Hardware Wallet
A Hardware Wallet lets you approve bitcoin payments without handing your private keys to your everyday computer. It protects access to money, not money stored inside a box. Checking its screen and keeping a safe backup matter just as much…
Watch-only Wallet
A Watch-only Wallet shows incoming payments and balances and can prepare unsigned transactions. It does not hold the private keys needed to spend. An accurate view requires the complete rules of your wallet and reliable blockchain data.
Coin Control
A wallet feature for choosing which funds you have received to use for a payment. It helps you manage fees and decide which funds to link publicly.
Change Address
An address in your own wallet that receives the unused remainder of a payment. It lets you spend part of an amount you received earlier and keep the rest.
Confirmation
A confirmation tells you that a payment has entered an accepted block. Later blocks bury it deeper in the history and usually make rewriting it harder. Pressing Send does not itself create a confirmation.
Double-spend
A double-spend attempts to use the same bitcoin funds in incompatible payments. Bitcoin permits only one of them in a valid history. The danger arises when a recipient delivers goods for a payment that ultimately loses.
Coinbase transaction
Who pays a miner when Bitcoin has no central treasury? The miner records the reward in a special transaction at the start of its block. Other nodes check that it claims no more than the rules allow. That transaction is called coinbase.
Bitcoin Script
Bitcoin Script records the conditions for spending a particular amount of bitcoin. A valid digital signature is usually required; sometimes several signatures or a time condition are involved. The wallet supplies the necessary data, and…
Soft Fork
A Soft Fork restricts behaviour that Bitcoin previously allowed. Older nodes can still accept the new blocks, but no longer check every condition themselves. This makes gradual upgrades possible while explaining the risk of outdated…
Hard Fork
A Hard Fork permits something Bitcoin's old rules prohibited. A new node may therefore accept a block that an old node rejects. If both groups continue independently, their payment histories diverge too; two lasting currencies do not appear…
BIP (Bitcoin Improvement Proposal)
A BIP sets out an idea publicly so people can discuss it and developers can implement the same design. Its number makes a particular document easy to refer to. The number alone does not show that the proposal is safe, supported or already…
Consensus Rules
The rules each Full Node uses to check transactions and blocks independently, without having to trust a miner or wallet provider.
Reorg
Even a confirmed payment can temporarily lose its confirmation. A Reorg happens when a node accepts a different valid branch of Bitcoin’s history, replacing the latest blocks it had been following.
Stale Block
A Stale Block is a valid Bitcoin block left on a side branch. No fraud is required: two miners can find blocks almost simultaneously, and the network later continues along just one of those branches.
ASIC Miner
An ASIC Miner makes vast numbers of attempts to find a new Bitcoin block. Here is what its performance means, why it consumes electricity, and why switching it on does not guarantee an income.
Mining Pool
A Mining Pool lets miners work together and receive smaller ongoing rewards instead of waiting to find a block themselves. It matters what the pool pays for, who holds unpaid funds, and who chooses the transactions.
Hashrate
Hashrate tells you how many mining attempts a machine can make per second. For the whole network, however, it is an estimate from discovered blocks: a moving chart need not mean thousands of machines are switching on or off.
Nonce
Nonce is a number that mining equipment changes while searching for a new Bitcoin block. Each change gives the calculation a different input and another opportunity to meet the mining rules.
Fee Rate
When you send bitcoin, you do not pay a percentage of the amount transferred. You pay for the space the transaction takes up in a block. Fee Rate expresses the price per unit of that space; wallets use it to gauge how strongly your…
Replace-by-Fee (RBF)
Replace-by-Fee (RBF) lets a pending Bitcoin transaction be replaced with one paying a higher fee. A wallet can use it to help a payment that has not reached a block yet; it cannot reverse an already confirmed payment.
CPFP (Child Pays for Parent)
Child Pays for Parent (CPFP) helps a pending Bitcoin payment through a follow-up transaction. The new transaction spends funds from the original and offers enough fees to make including both in a block attractive to a miner.
Timelock
A Timelock is a time condition in Bitcoin: it sets the earliest point when a transaction can confirm or a particular spending option can be used. It can enable delayed access to funds or a way to recover them if another party stops…
HTLC
An HTLC links payment to revealing the right secret and offers a recovery path if payment is not completed. In Lightning Network, this allows payments through intermediaries without relying solely on their promises. Protection still depends…
Payment Channel
A payment channel lets two parties make repeated payments without recording each one on the blockchain. What changes is their agreement about how the bitcoin is divided; the ability to settle on-chain gives that agreement force. Lightning…
Lightning Watchtower
When your Lightning node is offline, someone still needs to watch for a peer closing the channel with a balance that has already been revoked. A Lightning Watchtower can spot that attempt and act using information you supplied beforehand.
Lightning liquidity
Having money in a Lightning wallet does not mean you can receive the same amount. Liquidity describes how much can currently move in a particular direction through your payment channels. The amount matters, but so does which side of the…
Lightning Routing
You do not need a direct channel with everyone you pay over Lightning. A payment can pass through other nodes. Lightning Routing looks for a path with enough funds in the right direction and suitable fee and time conditions. A line on the…
Extended Public Key (xpub)
You want to see incoming payments on your phone without giving it the keys that can spend your bitcoin. An xpub helps do that: it lets software prepare addresses and monitor a particular part of a wallet without access to its private…
Output Descriptor
Recovering your keys does not always mean finding the right addresses. A wallet also needs the rules it originally used to create them. An Output Descriptor records those rules precisely so another compatible wallet can read them. It is…
PSBT
A computer can prepare a payment while the keys stay in a hardware wallet. PSBT carries the proposal and the information needed to check it between them; after approval, the device adds a signature. The same format helps when several people…
CoinJoin
Bitcoin payments are public, but a record need not reveal who owns each new output. CoinJoin uses that distinction: several people build one shared transaction. It can make their money harder to follow, without erasing history or promising…
Bitcoin Privacy
Paying someone with bitcoin should not mean showing them your entire financial life. Yet a public payment history can reveal more than you expect. Privacy starts with understanding what is visible, who knows you and which pieces of…
Pseudonymity
A Bitcoin address does not contain your name. A payment can still be connected to you through an order, an exchange account or an address published on a blog. Pseudonymity explains why having no name attached does not guarantee anonymity.
KYC
When a Bitcoin exchange asks for your ID or an explanation of where your money came from, you are encountering KYC. It is a customer check performed by a service, not registration with Bitcoin. It helps to understand what the check…
Self-custody
With self-custody, you hold the means to spend bitcoin instead of an account custodian. That independence brings responsibility: you need to recognize the right address, protect backups and be able to restore the wallet.
Custodial Exchange
An exchange can let you buy bitcoin in a few clicks. But if the exchange holds the keys, an app balance does not mean you can send the bitcoin yourself. A Custodial Exchange makes trading and storage convenient while leaving you dependent…
Satoshi
You do not need to buy a whole bitcoin. You can own and send small parts of one, called satoshis or sats. One bitcoin contains exactly 100000000 sat; switching your wallet from BTC to sats changes the display, not the amount of money.
Fiat money
Czech crowns in a bank account and euro banknotes are both fiat money. They are not vouchers for a fixed amount of gold. We use them because we get paid in them, know prices in them and expect someone else to accept them. To understand how…
Austrian economics
Why will one person pay fifty crowns for a coffee while another would not want it for free? How can rising bean prices affect a café that knows nothing about a failed harvest far away? Austrian economics starts with decisions made by real…
Sound money
Pavel sets aside money for a refrigerator he will need next year. Keeping the same number in his account is not enough: he needs it still to buy the fridge, the shop to accept it and the payment to arrive. Questions like these lie behind…
Knowledge network
The lines are the product. Each page includes curated relationships and automatically generated backlinks.