System Software ~ is the backbone of any computer. It consists of all the files and programs that work to make your computer operate as a computer. System software is automatically provided when you purchase a computer on the high street, and is installed along with the operating system.

Application Software ~ utilizes the technology provided by system software to allow specific programs to run on a computer.


Application  software and system software
There are system software and application software. 
System software is responsible for its internal activities. Without system software you won't be able to use a computer. Example: operation system, e.g. Windows, Linux, Android.

Application software is a secondary software - it allows the computer to perform tasks and run programs. Examples: word processors, spread sheets.