What is a Node?

In blockchain networks, nodes are the individual computers or servers that maintain copies of the distributed ledger, validate transactions, relay information, and collectively enforce the protocol rules, forming the fundamental infrastructure that enables decentralized networks to function without central coordination or authority.

Nodes come in various types with different responsibilities: full nodes independently verify all transactions and blocks against consensus rules while maintaining complete copies of the blockchain; light nodes verify block headers but rely on full nodes for detailed transaction data; and specialized nodes like mining nodes or validator nodes actively participate in block production and consensus.

The geographic and organizational distribution of nodes is critical to a blockchain's security and censorship resistance, as a diverse and widespread node network prevents any single entity or jurisdiction from controlling the system, creating the foundational resilience that makes blockchains valuable as neutral, global infrastructure.

Running a node represents one of the most direct ways to participate in blockchain networks, allowing operators to verify information independently rather than trusting third parties, contribute to network security and decentralization, and access blockchain data without relying on external service providers.

As blockchain technology evolves, node software continues to become more efficient and accessible through innovations like pruned nodes, snapshot syncing, and light client protocols, reducing the resources required to participate in network validation and making node operation more practical for a wider range of participants.