Catastrophic failure is a complete, sudden, often unexpected breakdown in a machine, electronic system, computer or network. Such a breakdown may occur as a result of a hardware event such as a disk drive crash, memory chip failure or surge on the power line. Catastrophic failure can also be caused by software conflicts or malware. Sometimes a single component in a critical location fails, resulting in downtime for the entire system. Well-engineered computers and networks are designed so that localized faults rarely precipitate catastrophic failures. Engineering practices such as graceful degradation and fault tolerance are elements of a sound fault-management platform. Graceful degradation is the ability of a system or network to maintain limited functionality even when a large portion of it has been destroyed or rendered inoperative. Fault-tolerant describes a computer system or component designed so that, in the event that a component fails, a backup component or procedure can immediately take its place with no loss of service