- Software is developed and engineered.
- Software doesn't "wear-out".
- Most software continues to be custom built.
Types of software
A layer 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 helps run the computer hardware and computer system. It includes a combination of the following:
- device drivers
- operating systems
- 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.
source : wikipedia