A system software component that is external to the operating system kernel. If the phrase is used to refer to the operating system itself, it is redundant because an operating system "is" software.

An operating system is a master control program that runs the computer system. In all environments, except for specialized scientific and process control applications, the operating system (OS) ...

Basically it’s an operating system that uses a Linux kernel, the WINE compatibility layer for Windows applications, and the ...

What are open-source operating systems? Underpinning an operating system, for example Windows on your PC or Android on your phone, is many, many lines of code. Allowing anyone to inspect the source ...