AN operating system exploits all the hardware resources of one or more processes and provide services to the system users. the operatingsystem control the application of processes.it is a user friendly computer.we have differnt operating systems like unix,mvs,windowsNt. an operating system will reside in mainmemory.it is kernel or nuclues.it is part of the mainmemory. an operating system is the interface btw a computerhardware and system users.it is a application software. the operatingsystems provide convenience,utility,efficiency to the computer.