A node is a computer that takes part in a cryptocurrency network by running its software. Nodes keep a copy of the BlockchainBlockchainA public ledger where transactions are grouped into blocks, each linked to the one before, so past records can't be altered without it showing., receive new transactions and blocks, check that they follow the rules and pass them on to other nodes.
What does a node do?
Picture thousands of auditors each going through the same set of books. None of them trusts the others. Each one checks that every TransactionTransactionA record of crypto moving from one wallet address to another, signed with the sender's private key and stored permanently on the blockchain. is properly signed and that nobody spends the same money twice. If a block breaks the rules, the nodes reject it, no matter who sent it.
There are a few kinds of node:
- A full node stores the whole chain and verifies every transaction since the beginning. For Bitcoin, that meant downloading more than 700 gigabytes of data the first time in 2026, and the chain keeps growing.
- A light node, as used in many mobile wallets, downloads only part of the data and relies on full nodes for the rest.
- Miners' and validators' nodes also create new blocks, through MiningMiningThe process in which computers compete to solve a puzzle so they can add the next block to the blockchain and earn new bitcoin and fees. or proof of stakeProof of stakeA consensus method where crypto is locked up as a stake for the right to create blocks, and anyone who cheats can lose part of that stake..
Why do nodes matter?
Nodes are what make a network decentralisedDecentralisationWhen power and responsibility are spread across many participants, instead of one bank, company or government controlling a system.. The more people run one, the harder it is to shut the network down or change its rules without broad agreement. Anyone can run their own Bitcoin node on an ordinary home computer, and then they don't have to trust anyone else to tell them what is true.
Everything in Myntkaup Learn is written and regularly reviewed by the Myntkaup editorial team. It is for education and is not investment advice. Editorial policy. Updated 18 October 2026.