How Does ‘Nakamoto Consensus’ Enforce the Longest Chain Rule?

Nakamoto Consensus, the mechanism used by Bitcoin, dictates that the legitimate chain is the one with the most cumulative Proof-of-Work (the 'longest chain'). Nodes continuously verify and extend this chain.

If a fork occurs, the network will eventually follow the chain that has the most computational effort invested, effectively discarding shorter, competing chains and enforcing the history of the longest chain.