Full node

A full node is a node that downloads and independently verifies the blockchain against all consensus rules, checking every block and transaction rather than trusting others. It typically stores a complete copy of the ledgers current state, letting it reject invalid blocks on its own. Full nodes are the backbone that enforces a networks rules.

A common misconception is that a full node must keep the entire history forever; some prune old data while still validating everything. Running one maximises self-verification but requires storage, bandwidth, and time to stay synced.