Definition of Fault tolerant:
Machine, equipment or system that has the ability to recover from a catastrophic failure without disrupting its operations. A fault tolerant computer system relies on technologies such as disk mirroring and redundant controllers. It also includes several redundant processors monitoring each other under a voting system so that if one processor fails, the other(s) will shut it down, call for human help, and continue data processing by taking over its load. Under more secure schemes, the entire system is duplicated (often at a remote location) to provide full backup in case the primary computer is destroyed.
Meaning of Fault tolerant & Fault tolerant Definition