Core blockchain and cryptocurrency network terms, including blocks, transactions, nodes, mempool, forks, confirmations and other concepts.

Consensus

The process of reaching agreement on valid blockchain state and history.

Details

Stale Block

A valid competing block that remains outside the current main chain.

Details

Smart Contract

A blockchain program that executes predefined logic and manages on-chain state.

Details

Consensus Mechanism

A set of rules defining how a network selects and validates blocks.

Details

Block Size

The amount of data contained in an individual blockchain block.

Details

Chain Reorganization

A replacement of part of the current chain with an alternative accepted history.

Details

Blockchain

A distributed ledger built from a sequence of cryptographically linked blocks.

Details

Mempool

A collection of pending transactions waiting for block inclusion.

Details

Light Node

A node designed to operate with reduced storage and processing requirements.

Details

Full Node

A node capable of independently validating blockchain data against protocol rules.

Details

Blockchain Node

A network participant that performs blockchain data, validation, or communication functions.

Details

Orphan Block

A block that has been excluded from the currently accepted chain.

Details

Hard Fork

A protocol change that introduces rules incompatible with the previous rule set.

Details

Soft Fork

A blockchain rule change that introduces stricter validity requirements.

Details

Transaction Output

A UTXO transaction element that creates funds for future spending.

Details

Transaction Input

A reference to a previous unspent output used by a new transaction.

Details

Transaction

A signed operation that changes blockchain state according to network rules.

Details

Block Weight

A protocol-specific metric used to determine the effective size of a block.

Details

Block Height

A number identifying the position of a block in the chain.

Details

Block Header

The metadata portion of a block used for identification and validation.

Details

Genesis Block

The first block of a blockchain and the starting point of its history.

Details

Fork

A protocol-rule change or divergence between blockchain histories.

Details

Transaction Fee

A fee associated with processing and including a transaction in the blockchain.

Details

Block Time

A time-based measure describing block production or a block timestamp.

Details

Block

A blockchain data unit containing transactions and chain metadata.

Details