blockchain
Sign in to saveA blockchain is a distributed ledger with growing lists of records (blocks) that are securely linked together via cryptographic hashes. Each block contains a cryptographic hash of the previous block, a timestamp, and transaction data (generally represented as a Merkle tree, where data nodes are represented by leaves). Since each block contains information about the previous block, they effectively form a chain (viz. linked list data structure), with each additional block linking to the ones before it. Consequently, blockchain transactions are resistant to alteration because, once recorded, the
AI overview
A blockchain is a digital record-keeping system where information is stored in linked blocks secured by cryptography, making it extremely difficult to alter past records without detection. It matters because this structure creates a permanent, tamper-resistant way to track transactions across a distributed network without needing a central authority to verify them.
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Article
41 sectionsContents
- History
- Structure and design
- Blocks
- Block time
- Hard forks
- Decentralization
- Finality
- Openness
- Permissionless (public) blockchain
- Permissioned (private) blockchain
- Disadvantages of permissioned blockchain
- Blockchain analysis
- Standardisation
- Centralized blockchain
- Types
- Public blockchains
- Private blockchains
- Hybrid blockchains
- Sidechains
- Consortium blockchain
- Uses
- Cryptocurrencies
- Smart contracts
- Financial services
- Games
- Supply chain
- Domain names
- Other uses
- Blockchain interoperability
- Energy consumption concerns
- Academic research
- Adoption decision
- Collaboration
- Blockchain and internal audit
- Testnet
- Mainnet
- Journals
- See also
- References
- Further reading
- External links
A blockchain is a distributed ledger with growing lists of records (blocks) that are securely linked together via cryptographic hashes. Each block contains a cryptographic hash of the previous block, a timestamp, and transaction data (generally represented as a Merkle tree, where data nodes are represented by leaves). Since each block contains information about the previous block, they effectively form a chain (viz. linked list data structure), with each additional block linking to the ones before it. Consequently, blockchain transactions are resistant to alteration because, once recorded, the data in any given block cannot be changed retroactively without altering all subsequent blocks and obtaining network consensus to accept these changes.
Blockchains are typically managed by a peer-to-peer (P2P) computer network for use as a public distributed ledger, where nodes collectively adhere to a consensus algorithm protocol to add and validate new transaction blocks. Although blockchain records are not unalterable, since blockchain forks are possible, blockchains may be considered secure by design and exemplify a distributed computing system with high Byzantine fault tolerance.