software, commonly known as programs, consists of all the electronic instructions that tell the hardware how to perform a task.these instructions come from a software developer in the from that will be accepted by the operating system that they are based on. for example, a program that is designed for the windows operating system only work for that operating system . compatibility of software will vary as the design of the software and operating system differ. a software that is designed for windows xp may experience compatibility issue when running under windows 2000 or vt