# Blockchain

Source URL: https://support.dxp.blockstream.com/education/glossary/blockchain
Updated: 2026-05-26T17:15:15.000Z
Letter: B

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A blockchain is a publicly auditable ledger in which transactions are grouped into cryptographically linked [blocks](https://support.dxp-staging.blockstream.com/education/glossary/block) and agreed upon by a decentralized network of nodes running proof-of-work consensus.

Because every full node keeps its own copy of the chain and verifies each block, there is no central point of failure. Altering a past transaction would require re-doing the [proof-of-work](https://support.dxp-staging.blockstream.com/education/glossary/proof-of-work) for that block and all subsequent blocks, then convincing a majority of the network to accept the change—an attack considered economically infeasible.

Key properties include:  
• [**Decentralized**](https://support.dxp-staging.blockstream.com/education/glossary/decentralization) \- anyone can run a [node](https://support.dxp-staging.blockstream.com/education/glossary/bitcoin-node); no single party controls the history.  
• **Immutable** \- once confirmed, a transaction cannot be edited or deleted.  
• **Transparent yet pseudonymous** \- all Bitcoin transactions are visible to anyone, while user identities are represented only by addresses.

By solving the double-spend problem without a trusted intermediary, the blockchain enables peer-to-peer electronic cash and lays the foundation for innovations such as the [Lightning Network](https://support.dxp-staging.blockstream.com/education/glossary/lightning-network) and tokenization layers like [Liquid](https://support.dxp-staging.blockstream.com/education/glossary/liquid-network).

Navigation: Blockstream Help Center > Education > Glossary > Blockchain

## Related Terms in This Letter
- [Blind oracle](https://support.dxp.blockstream.com/education/glossary/blind-oracle)
- [Borromean ring signatures](https://support.dxp.blockstream.com/education/glossary/borromean-ring-signatures)
- [Bitcoin Script](https://support.dxp.blockstream.com/education/glossary/bitcoin-script)
- [BitVM](https://support.dxp.blockstream.com/education/glossary/bitvm)
- [BOLT12](https://support.dxp.blockstream.com/education/glossary/bolt12)
- [Bitcoin](https://support.dxp.blockstream.com/education/glossary/bitcoin)
- [Bitcoin Node](https://support.dxp.blockstream.com/education/glossary/bitcoin-node)
- [Bitcoin Core](https://support.dxp.blockstream.com/education/glossary/bitcoin-core)
- [Bulletproofs](https://support.dxp.blockstream.com/education/glossary/bulletproofs)
- [Blind signatures](https://support.dxp.blockstream.com/education/glossary/blind-signatures)
- [Blockchain](https://support.dxp.blockstream.com/education/glossary/blockchain) (current)
- [Block](https://support.dxp.blockstream.com/education/glossary/block)
- [Block Header](https://support.dxp.blockstream.com/education/glossary/block-header)
- [Block Height](https://support.dxp.blockstream.com/education/glossary/block-height)
- [Blockchain Explorer API](https://support.dxp.blockstream.com/education/glossary/blockchain-explorer-api)
- [Broadcast Transaction](https://support.dxp.blockstream.com/education/glossary/broadcast-transaction)