What is a blockchain? A plain-English guide based on NIST's overview
How a blockchain works, block by block: hashes, signatures, consensus, permissionless vs permissioned networks, and the limits that marketing usually leaves out.
Basics
Blockchain, bitcoin, Ethereum, DeFi, NFTs and the words you keep hearing, explained from primary sources without hype.
30 guides
Public keys, private keys and addresses: what's the difference in crypto?
How crypto wallets use a private key, a public key and an address, which one you can share, how signatures prove ownership and why a lost key is final.
What is bitcoin? How it works, who controls it and how it's regulated
Bitcoin explained from its original white paper and source code: mining, the 21 million cap, keys and wallets, and how US, UK and Canadian authorities treat it.
The bitcoin white paper explained, section by section, in plain English
A plain-English walk through Satoshi Nakamoto's nine-page bitcoin white paper: double spending, timestamps, proof of work, incentives, privacy and what it left out.
Satoshis, bits and BTC: bitcoin's units explained (and why you don't need a whole bitcoin)
How bitcoin divides into 100 million satoshis, what mBTC, bits and sats mean, how fees are quoted in sat/vB, Lightning's millisatoshis and simple conversions.
What is Ethereum? ETH, smart contracts and gas, explained simply
What Ethereum is, how it differs from bitcoin, what ETH is for, how smart contracts and gas fees work, and what changed when it moved to proof of stake in 2022.
What is a smart contract? How blockchain programs work, and their risks
What smart contracts are, the vending machine idea behind them, what they do, why their code can't be changed after launch, the main risks and their legal status.
What is a blockchain oracle? How smart contracts get real-world data, and the oracle problem
Why smart contracts can't read the outside world on their own, how oracles bring in prices and other data, centralized vs decentralized oracles and the risks.
Ethereum's recent upgrades explained: Dencun, Pectra, Fusaka and what comes next
What Ethereum's recent upgrades changed: cheaper layer 2 data with Dencun and Fusaka, smart accounts and staking changes in Pectra, and the roadmap ahead.
Ethereum gas fees explained: what you pay, why it changes, and how to pay less
How Ethereum gas fees work: gas units, gwei, the burned base fee, tips, max fee and gas limit, why failed transactions still cost you, and how to pay less.
What is a layer 2? Rollups explained, and why they make Ethereum cheaper
What layer 2 networks are, how optimistic and zero-knowledge rollups work, why fees are lower, the week-long withdrawal wait and the risks to check first.
Crypto bridges explained: how tokens move between blockchains, and why bridges get hacked
What blockchain bridges do, lock-and-mint and other designs, trusted vs trustless bridges, why bridges are behind some of the biggest hacks and how to stay safe.
Bitcoin vs Ethereum: the real differences, explained simply
Bitcoin and Ethereum compared: what each is for, mining vs staking, supply, fees, speed, what you can build, how they're regulated and taxed, and the risks.
Bitcoin mining explained: how it works, the difficulty adjustment, pools and how mining income is taxed
What bitcoin miners do, how proof of work and the difficulty adjustment keep blocks at about 10 minutes, solo vs pool mining, and how mining is taxed.
Proof of work vs proof of stake: how blockchains agree, and the trade-offs
How proof of work (bitcoin) and proof of stake (Ethereum) secure a blockchain, how attacks are punished, energy use, decentralization and what each side argues.
What is a 51% attack? How blockchains can be attacked, and what an attacker can't do
What a 51% attack is on proof-of-work and proof-of-stake blockchains, what an attacker could and couldn't do, why confirmations matter, and what it means for you.
What is a hard fork? Soft forks, chain splits and what happens to your coins
What hard and soft forks are, why blockchains split, what happened with Ethereum Classic, whether you get new coins and how the IRS and HMRC tax them.
Could quantum computers break bitcoin? What's at risk and what's being done
Why quantum computers could one day break crypto wallet signatures, what's less at risk, NIST's post-quantum standards and what bitcoin and Ethereum are doing.
How to send crypto safely: addresses, networks, fees and the mistakes you can't undo
A checklist for sending bitcoin, ether or stablecoins safely: copying addresses, the right network, fees, test transactions, confirmations and address poisoning.
How to use a block explorer to check a crypto transaction
What a block explorer is, how to look up a transaction ID or address, what pending, failed and confirmed mean, and how explorers help with fees, scams and taxes.
Bitcoin transaction stuck or unconfirmed? Why it happens and how to speed it up
Why a bitcoin transaction can sit unconfirmed for hours or days, how fees and the mempool work, and how replace-by-fee and child-pays-for-parent can speed it up.
The Lightning Network explained: fast, cheap bitcoin payments and their trade-offs
How bitcoin's Lightning Network uses payment channels for near-instant, low-fee payments, how channels open and close, invoices, custodial wallets and the risks.
Is crypto legal? The rules for owning, buying and trading crypto in the US, UK and Canada
Yes, owning crypto is legal in the US, UK and Canada, but it isn't legal tender. Who regulates platforms, what's banned, and what legal doesn't mean.
What is DeFi? Decentralized finance explained, with the risks regulators see
What decentralized finance is, what people use it for, how it differs from banks and exchanges, and the risks highlighted by the Financial Stability Board.
What is a DAO? Decentralized autonomous organizations explained, with their legal risks
What a DAO is, how token voting works, what happened to The DAO in 2016, why the SEC said its tokens were securities, and the CFTC case that held a DAO liable.
What are NFTs? What you actually own, the risks, and how they're taxed
Non-fungible tokens explained: what an NFT is and isn't, what buying one gives you, the common scams, and how the IRS may treat NFTs as collectibles.
What is a CBDC? Digital dollars, digital pounds and where the US, UK and Canada stand
What a central bank digital currency (CBDC) is, how it differs from cash, bank money, stablecoins and bitcoin, and the official position in the US, UK and Canada.
Memecoins explained: what they are, why they're so risky, and what the SEC says
What memecoins are, why their prices swing so wildly, what the SEC said in 2025 and 2026, how losses are treated for tax, and the scams to watch for.
Crypto airdrops explained: free tokens, tax rules and airdrop scams
What a crypto airdrop is, why projects give tokens away, how the IRS and HMRC tax them, and how fake airdrops are used to drain wallets.
Crypto glossary: 57 terms explained in plain English
From address to yield: the crypto words you keep hearing, explained in one or two sentences each, with links to our full guides and the official sources.