A cryptographic system using a pair of keys: a public key (shared openly) and a private key (kept secret). Data encrypted with one can only be decrypted with the other.

Public-key cryptography based on elliptic curves over finite fields. Bitcoin uses ECC to generate secure key pairs with relatively small key sizes.

Digital signature algorithm used by Bitcoin to prove ownership of funds. A user signs a transaction with their private key; others verify it using the public key.

An alternative digital signature scheme introduced via Taproot. Provides improved efficiency, better privacy, and enables signature aggregation.

A cryptographic hash function used in Bitcoin's proof-of-work algorithm. Produces a 256-bit output and is computationally secure against known attacks.

A binary tree where each leaf is a hash of data, and each parent is a hash of its children. The Merkle Root is the single top hash representing all transactions in a block.

An arbitrary number that miners adjust during mining to find a hash below the required difficulty target.

A deterministic function mapping arbitrary input to a fixed-size output. Designed to be irreversible and collision-resistant.

A consensus mechanism where miners solve computationally difficult puzzles to add a block. Secures the network by making manipulation costly.

Recalibrates mining difficulty every ~2016 blocks (~2 weeks) to ensure blocks are produced roughly every 10 minutes.

A collection of validated transactions grouped together and added to the blockchain. Each block references the previous one, forming a chain.

The very first block in the Bitcoin blockchain, created by Satoshi Nakamoto in 2009.

The block reward is the incentive given to miners (new bitcoins + fees). The coinbase transaction is the first TX in a block, creating new coins for the miner.

A situation where a different chain becomes the longest, causing previously confirmed blocks to be replaced. Nodes always follow the chain with the greatest accumulated proof-of-work.

A signed instruction that transfers bitcoin from one address to another. Every transaction references previous unspent outputs as inputs and creates new outputs.

Unspent Transaction Output. The fundamental accounting unit in Bitcoin. Your balance is the sum of all UTXOs assigned to your addresses.

Bitcoin's scripting language. ScriptPubKey locks funds; ScriptSig unlocks them. Together they validate ownership and enable conditional spending.

Multisig requires M-of-N signatures to spend. Timelock restricts spending until a block height or time, enabling smart contract-like conditions on Bitcoin.

A Layer 2 payment network built on Bitcoin. Enables near-instant, ultra-low fee transactions by routing payments through a network of payment channels.

A two-party off-chain agreement secured by a multisig on-chain. Parties can transact freely; only the opening and closing transactions are recorded on-chain.

Hash Time-Locked Contract. The cryptographic building block of Lightning routing — funds release only if a preimage is revealed within a time limit.

A node is any computer participating in the Bitcoin network. A full node stores the complete blockchain and independently validates every transaction and block, requiring no trust in third parties.

SPV (Simplified Payment Verification) lets lightweight clients verify transactions using only block headers. P2P means nodes communicate directly without central servers, ensuring censorship resistance.

The process of validating transactions and securing the network by solving computational puzzles.

The total computational power used by miners, measured in hashes per second.

Application-Specific Integrated Circuit. Specialized hardware designed specifically for Bitcoin mining, far more efficient than general-purpose hardware.

A group of miners who combine their computational resources and share rewards proportionally.

The degree of variation in Bitcoin's price over time.

The ease with which Bitcoin can be bought or sold without significantly affecting its price.

A real-time list of buy and sell orders on an exchange.

The difference between the highest buy price and the lowest sell price.

The practice of exploiting price differences of Bitcoin across different markets for profit.

The U.S. regulator that oversees securities markets and determines whether certain crypto assets qualify as securities.

A U.S. regulator that treats Bitcoin as a commodity and oversees derivatives markets.

Switzerland's financial regulator overseeing financial institutions and crypto compliance.

A set of laws and procedures designed to prevent money laundering activities.

A process used by financial institutions to verify the identity of their clients.

A regulation requiring crypto service providers to share sender and receiver information during transactions.

A comprehensive regulatory framework for crypto assets in the European Union.

The central banking system of the United States, responsible for monetary policy.

The central bank responsible for the euro and monetary policy in the Eurozone.

A tool that manages private keys and allows users to send, receive, and store Bitcoin.

A secret cryptographic key that grants the owner full control over their Bitcoin. Whoever holds the private key owns the funds.

A cryptographic key derived from the private key, used to generate a wallet address for receiving Bitcoin.

A 12 or 24 word backup phrase that can restore a Bitcoin wallet. Never share this with anyone.

Storing Bitcoin private keys offline, away from internet access, to protect against hacking.

A Bitcoin wallet connected to the internet, offering convenience but higher vulnerability to attacks.

A wallet where a third party (like an exchange) holds the private keys on behalf of the user.

A wallet where the user holds their own private keys, giving full ownership and responsibility over their funds.

A term meaning to hold Bitcoin long-term regardless of price fluctuations, originally a misspelling of "hold."

Fear of Missing Out — the anxiety that drives investors to buy into a rising market out of fear they'll miss gains.

Fear, Uncertainty, and Doubt — negative sentiment or misleading information spread to cause panic selling.

An individual or entity holding a large amount of Bitcoin, capable of influencing the market with their trades.

Slang for holding Bitcoin through extreme volatility without selling, showing strong conviction.

Slang for selling Bitcoin quickly during price drops, showing low conviction or panic selling behavior.

An asset that retains its value over time. Bitcoin is often compared to gold as a store of value.

An asset used to facilitate trade. Bitcoin can function as money to buy goods and services.

A standard measure for pricing goods and services. Satoshis (sats) are the smallest unit of Bitcoin.

A metric comparing existing supply to new production.

An increase in money supply reducing purchasing power.

A decrease in money supply or increase in purchasing power.

An attack where a single entity controls more than half of the network's mining power.

An attack where a user creates multiple fake identities to influence the network.

An attack that isolates a node from honest peers.

Spending the same Bitcoin more than once.

Reusing a valid transaction in a different context.

A tool that manages private keys and allows users to send and receive Bitcoin.

A secret cryptographic key that allows spending Bitcoin.

A key derived from the private key used to generate Bitcoin addresses.

A human-readable set of words used to back up and restore a wallet.

Storing private keys offline to reduce hacking risk.

A wallet connected to the internet.

A wallet where a third party controls the private keys.

A wallet where the user controls their own private keys.

A term meaning to hold Bitcoin long-term despite volatility.

Emotional bias causing investors to buy due to fear of missing gains.

The spread of negative information to influence sentiment.

An entity holding a large amount of Bitcoin capable of influencing the market.

An investor who holds assets through extreme volatility.

An investor who sells quickly due to fear.