It is a set of programs that enables the hardware to perform a specific task. All the programs that run the computer are software. Software is of two types; system software and application software.
1) System Software
System software is the main software that runs the computer. When you turn on the computer it activates the hardware and controls and coordinates their functioning. The application programs are also controlled by system software. Operating system is an example of system software.
Operating system is the system software that works as an interface to enable the user communicate with the computer. It manages and coordinates the functioning of hardware and software of the computer. The commonly used operating systems are Microsoft Windows, Linux and Apple Mac OS X
2) Application Software
Applications software is a set of programs designed to perform a specific task. It does not control or coordinate the working of computer. A computer can run without application software. Application software can be easily installed or uninstalled as required. Microsoft Office Suite, Adobe Photoshop and any other software like payroll software or income tax software are application software.