Bitcoin & Blockchain, Explained Simply

Bitcoin is money that runs on the internet without a bank, a CEO, or a government controlling it. Instead, thousands of computers around the world keep one shared record of who owns what, and a clever mix of cryptography and incentives keeps that record honest. Below is the whole thing, explained without jargon.

Read explainer →

A blockchain is a list of records that is copied across many computers and locked together so tightly that changing one old entry would break everything after it. That is what makes it trustworthy without a trusted middleman.

Read explainer →

SHA-256 is the cryptographic "fingerprint machine" at the heart of Bitcoin. Feed it any data and it returns a fixed 64-character code that is unique to that data, impossible to reverse, and changes completely if you alter even one letter.

Read explainer →

Bitcoin replaces usernames and passwords with a pair of keys. One you can share with the whole world, the other you must guard with your life. Together they let you receive money publicly and spend it privately, with no bank in between.

Read explainer →

Mining is how new bitcoin is created and how the network agrees on history. Miners burn electricity to win a global guessing game; the winner writes the next block and is paid in fresh bitcoin. It sounds wasteful, but that cost is exactly what makes Bitcoin secure.

Read explainer →

Thousands of strangers who do not trust each other somehow agree on a single, shared truth about who owns what, with no referee. The mechanism that makes this possible is called Nakamoto consensus, and it is Bitcoin’s real breakthrough.

Read explainer →

A node is a computer running Bitcoin software that keeps its own full copy of the blockchain and checks every rule for itself. Nodes are the network’s referees, and anyone, including you, can run one.

Read explainer →

When you send Bitcoin, you are not "moving" a coin like a file. You are signing a message that consumes some of your previous received amounts and creates new ones for the recipient. Here is exactly what happens in the few seconds and minutes after you hit send.

Read explainer →

Bitcoin does not store your balance as a single number like a bank account. Instead it tracks individual chunks of value called UTXOs. Once you see Bitcoin as digital cash rather than a bank balance, fees, change and privacy suddenly make sense.

Read explainer →

A Merkle tree is the clever trick that lets a lightweight phone wallet confirm a payment is in a block without downloading the entire blockchain. It compresses thousands of transactions into one tiny fingerprint.

Read explainer →

Roughly every four years, the amount of new bitcoin created per block is cut in half. This pre-programmed "halving" is how Bitcoin enforces scarcity, and it is one of the most-watched events in all of finance.

Read explainer →

People use "Bitcoin" and "blockchain" as if they were the same word, they are not. Getting this straight is the fastest way to sound informed and to see through a lot of crypto marketing hype.

Read explainer →

Bitcoin's main chain is secure but slow and, at busy times, costly, fine for large transfers, impractical for buying coffee. The Lightning Network is the fix: a layer built on top of Bitcoin for instant, near-free payments. It is how Bitcoin becomes usable as everyday money, and the idea behind it is more intuitive than it sounds.

Read explainer →

Payment channels are the engine of the Lightning Network. The idea, two parties locking funds and then updating who owns what without touching the blockchain, sounds like magic, but it rests on clever, verifiable Bitcoin transactions. Understanding channels demystifies how Lightning can be both instant and secure, and what "liquidity" really means.

Read explainer →

Bitcoin's base layer prizes security and decentralization over speed, so to scale it for billions of users, extra layers are built on top. "Layer 2" is the umbrella term for these, with the Lightning Network the most famous. Understanding the Layer 2 landscape shows how Bitcoin can stay rock-solid at its core while becoming fast and flexible above.

Read explainer →

A common criticism of Bitcoin is that it processes only a handful of transactions per second, far fewer than Visa. But that limit is a deliberate choice, not a flaw, rooted in a fundamental trade-off every blockchain faces. Understanding the "scalability trilemma" explains why Bitcoin scales the way it does, and why bigger blocks are not the easy answer they seem.

Read explainer →