“The ability of a system, network, or process, to handle a growing amount of work in a capable manner or its ability to be enlarged to accommodate that growth.”

“The property that enables a system (often computer-based) to continue operating properly in the event of the failure of (or one or more faults within) some of its components.”

“High availability is a system design approach and associated service implementation that ensures a prearranged level of operational performance will be met during a contractual measurement period.”