Types of Nodes

Nodes on a Blockchain

A node is any computer or device that participates in a blockchain network by maintaining a copy of the blockchain and helping to validate and relay transactions.

Think of it like this: if the blockchain is a shared ledger, nodes are the individual participants each holding and maintaining their own copy of that ledger.

What Nodes Do

Store data — Keep a full or partial copy of the blockchain's transaction history
Validate transactions — Verify that new transactions follow the network's rules
Propagate data — Broadcast new blocks and transactions to other nodes
Maintain consensus — Help the network agree on the "true" state of the chain

Types of Nodes

Full Nodes

Download and independently verify the entire blockchain. They are the backbone of the network trustless, self-sovereign, and most secure.

Examples: Bitcoin Core, Geth (Ethereum).

Light Nodes (SPV)

Only download block headers, not full transaction data. They rely on full nodes for verification. Used mostly in mobile wallets.

Validator / Miner Nodes

Participate in block production miners in Proof of Work (PoW), validators in Proof of Stake (PoS). They propose and confirm new blocks and earn rewards.

Archive Nodes

Store the entire history of the blockchain including all historical states not just the current state. Essential for blockchain explorers like Etherscan.

RPC Nodes

Expose an API endpoint so dApps and developers can query blockchain data without running their own node (e.g., Infura, Alchemy, QuickNode).