What are the three differences of an operating system from an ordinary user program?

Answer 1

The operating system (or OS) is the software that make the computer work. There are several different OS's out there. These include Windows, the Mac OS, and the various forms of Unix among others. The type of computer you have will largely determine the type of OS that you can install on it. Most Intel/AMD based PC's come with Windows installed. Macintoshes come with the Mac OS. Various forms of Unix have been written to run on both platforms and the most recent Macs (the Intel based ones) can also run Windows though you have to provide and install your own copy of it if you want to do this.

The application software consists of the programs that actually let you do things with your computer. These applications are written to run under the various operating systems. These include things like your word processing programs, spread sheets, email clients, web browser, games, etc. A program that is written to run under Mac OS won't run under Windows and a program that is written for Windows won't run under Mac OS. However, many programs, such as most of the Microsoft Office suite of programs, are written in both Mac and Windows versions, but you still have to have the right version for your OS.

So, the operating system of a computer is the software that allows the computer work. It provides the framework under which the applications run. The applications are the software that actually allows the user to do something with the computer. Without the applications, all you can do is change settings and navigate among the folders