All terms
A computer that keeps a copy of the blockchain and checks the rules.
A node downloads blocks, verifies that every transaction follows the rules, and keeps its own copy of the ledger. It does not take anyone's word for what happened. It checks.
Running a node is how you stop trusting third parties. Most people never do it, and that is fine, but the fact that anyone can is what keeps the network honest.
A Bitcoin full node stores the entire history and will reject a block that tries to create coins out of thin air, no matter who sent it.
That running a node earns you money. Miners and validators earn rewards; an ordinary node earns nothing. What it buys you is the ability to check the chain yourself rather than trusting somebody else's answer.
Common questions
Do I need to run a node to use crypto?
What does running a node cost?
Where to go next
More foundations terms
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