User Application Operating system Hardware

This is a structure showing where Operating System is located on generally used software systems on desktops. Practical computer systems divide software systems into three major classes: system software, programming software and application software, although the distinction is arbitrary, and often blurred.

System software

System software helps run the computer hardware and computer system. It includes a combination of the following:

· device drivers;

· operating systems;

· servers;

· utilities;

· windowing systems.

The purpose of systems software is to unburden the applications programmer from the often complex details of the particular computer being used, including such accessories as communications devices, printers, device readers, displays and keyboards, and also to partition the computer's resources such as memory and processor time in a safe and stable manner. Examples are- Windows XP, Linux, and Mac OS X.

Programming software

Programming software usually provides tools to assist a programmer in writing computer programs, and software using different programming languages in a more convenient way. The tools include:

· compilers

· debuggers

· interpreters

· linkers

· text editors

An Integrated development environment (IDE) is a single application that attempts to manage all these functions.

Application software

Application software allows end users to accomplish one or more specific (not directly computer development related) tasks. Typical applications include:

· industrial automation

· business software

· computer games

· quantum chemistry and solid state physics software

· telecommunications (i.e., the internet and everything that flows on it)

· databases

· educational software

· medical software

· military software

· molecular modeling software

· image editing

· spreadsheet

· Word processing

· Decision making software

Application software exists for and has impacted a wide variety of topics.