How Does the “Longest Chain Rule” Resolve Discrepancies between Full Nodes?

The longest chain rule, often referred to as the "Nakamoto Consensus," dictates that in the event of a fork or disagreement, full nodes accept the chain with the most cumulative Proof-of-Work (PoW) difficulty, which is usually the longest chain. This mechanism ensures network synchronization and prevents conflicting transaction histories from persisting.

It incentivizes miners to build on the accepted chain.