System software refers to the files and programs that make up a computer’s operating system. System files include libraries of functions, system services, drivers for printers and other hardware, system preferences, and other configuration files. The programs that are part of the system software include assemblers, compilers, file management tools, system utilities, and debuggers.

The system software is installed on a computer when the operating system is installed. Users can update the software by running programs such as “Windows Update” for Windows or “Software Update” for Mac OS X. However, unlike application programs, system software is not meant to be run by the end-user. For example, while you might use your Web browser every day, you probably don’t have much use for an assembler program (unless, of course, you are a computer programmer).