Noun | 1. | ![]() backup system - a computer system for making backups auxiliary equipment, off-line equipment - electronic equipment not in direct communication (or under the control of) the central processing unit platform - the combination of a particular computer and a particular operating system system - instrumentality that combines interrelated interacting artifacts designed to work as a coherent entity; "he bought a new stereo system"; "the system consists of a motor and a small computer" |