System software makes the computer system available for use. It manages the computer resources. It runs at the most basic level of computer and thus it is called “low-level” software.
It is one of the two categories of software. The other one is application software.
Various examples of system software are operating system(OS), BIOS, device firmware, certain system utility software which helps to configure, optimize and maintain the computer, programming software such as assemblers, compilers and debuggers etc.