A shared, immutable digital ledger where transactions are recorded and assets are tracked in a distributed network. An asset can be tangible (a property, car, equipment, artwork, etc.) or intangible (intellectual property, patents, copyrights, branding). Virtually, anything that carries value can be recorded and tracked and also traded on a blockchain network.

On a blockchain, all network participants have access to the shared digital ledger and its record of transactions. Through the ledger, transactions are recorded only once, eliminating repetition and the duplication of effort. No participant can alter or tamper with a transaction after it’s been validated and recorded to the shared ledger. In the case of faulty records, a new transaction must be recorded to reverse the error, and original and correcting transactions are then clearly maintained for transparency.

A blockchain data structure that consists of a number of blocks linked to each other. A block is part of ordered records listed on a distributed database (the blockchain) where it is linked to other blocks using cryptography. The elements of a block are a cryptographic hash of the previous block, a timestamp, and transaction data.

The structure represents a decentralized, distributed and public digital ledger where transactions across a network subject to a consensus building process. The records cannot be adjusted retroactively without adjusting all subsequent blocks and the consensus established across the respective blocks. Network nodes construct transactions into blocks, and if the transactions are successfully validated by the blockchain, blocks will be appended to the blockchain. Each block contains a number of transactions which represent the activity that’s recorded on the blockchain.

Validation (or mining) is the process of selecting transactions for inclusion into a block. It is performed by a node on the network known as a validator or miner. Nodes aggregate the transactions which are submitted to the blockchain. After validation, transactions are proposed to the next block on the blockchain. Selection of a block depends on the consensus mechanism adopted by the network. Most public networks use proof of stake (PoS), but certain others use proof of work (PoW), notably the Bitcoin network.