What is Byzantine Fault Tolerance (BFT)?

Byzantine Fault Tolerance (BFT) refers to a blockchain network's ability to reach consensus and continue operating even if some of the nodes in the network fail to respond or respond with incorrect information. A network that is Byzantine Fault Tolerant solves the Byzantine Generals' Problem, a situation in which all parties must agree but one or more parties are unreliable. Most actively used blockchain consensus mechanisms are Byzantine Fault Tolerant.