What is Operating System?

Operating System is a System Software.  So Many People give many own views regarding Operating System. They all views Define the Operating System Like:

“Operating System Consist of Program and Data that run on Computer, Manage Computer Hardware.”

“Operating System enables the Computer Hardware to Communicate and Operate with the Computer Software.”

“Operating System Provide a Friendly Environment to user for use computer hardware and run application programs easily”

We can use following Structure of System for understand existence of The Operating System in Computer.

 Structure of Operating System

 Above Structure of Operating System have Four Layer.

1. Hardware : Hardware Consist of Hardware Devices of Computer like CPU, Hardisk, I/O Devices, Main Memory(RAM(Random Access Memory )).
2. Software (Operating System) : Operating System Software Includes Process Management Routines, Memory Management, I/O Control Routine, File Management Routines. 
3. System Programs : This Layer of Compilers, Assemblers, linker etc.
4. Application Programs : This Customize Programs dependent on users needs. Like Tally, Ms office etc.  

  Now, We can say that "Computer is useless without Operating System."

Some name of Operating System is "DOS (Disk Operating System), UNIX, Linux, Windows 95, Windows NT, Windows 98, Windows 2000, Windows ME (Millennium Edition), Windows XP, Windows Vista, Windows 7, Mac Os etc."