"A mainframe or personal computer (PC) based operating system software (or firmware) specific to the central processing unit (CPU) incorporated into a general-purpose fluoroscopic x-ray system configuration. This includes the software or firmware based programs and routines supplied by the computer manufacturer that drive a specific computer in the performance of its tasks and assists the operators, applications programmers and programs with various supporting functions. A proprietary name and a ""version number"" are commonly used identify different operating system versions."