Blocky saysByzantine Fault Tolerance lets a network agree even if some nodes are malicious or faulty.
The Byzantine Generals Problem asks: how do honest participants reach agreement when some are traitors sending conflicting messages? BFT consensus (PBFT, Tendermint) tolerates up to ~1/3 faulty nodes and reaches instant finality once a quorum votes — no waiting for confirmations. It underpins many newer chains (Cosmos) where fast finality matters more than maximal node count.
Power-ups you unlock
Agree despite malicious/faulty nodes
Tolerates up to ~1/3 bad actors
PBFT/Tendermint give instant finality
Powers Cosmos and many newer chains
Double-Spend Dan attacks — common mistakes
Assuming BFT scales to unlimited validators
Confusing probabilistic (PoW) with instant (BFT) finality
Ignoring the 1/3 fault threshold
Boss battleExplain the ~1/3 fault tolerance and what "instant finality" buys you.
Example code
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<body style="background:#06040d;color:#e6e0ff;font-family:monospace;padding:20px"><pre>tolerate < 1/3 traitors → quorum vote → final
no "wait for confirmations" — finality is instant</pre></body></html>