Introduction and Role of Operating Systems

Introduction to Operating System

The operating system (OS) is an integrated set of programs that controls the resources like CPU, memory, I/ O devices of the computer system. The primary goal of an operating system is to maximize the productivity of a computer system by the operating system by operating it in the most effective and efficient manner and minimizing the amount of human intervention required. It provides an interface to its users, which is more convenient to use than the bare machine.

The two primary objectives of an operating system are:

·       Making a computer system convenient to use.

·       Managing the resources of the computer system.

An operating system is a collection of programs that controls the overall operation of the computer system. The operating system controls and coordinates the use of the hardware among the various application programs for the various users. So it acts as an interface between the user and the computer hardware.

Role of operating system

The operating system (OS) is a set of programs that manage computer hardware resources and provide common services for application software. The OS coordinates the function performed by the computer hardware, including the CPU, input/ output devices, secondary storage device, and the computer hardware, including the CPU, input/ output devices, secondary storage device, and communication and network equipment. It also keeps track of files and directories on the disks and controls peripheral devices such as disk drivers and printers.

·       It is a master’s program that controls the computer system.

·       It acts as an intermediary between the user and the computer hardware.

·       It provides an environment in which a user can execute other application programs in a convenient and effective manner.

·       It hides the complexities of the hardware from the user.

·       It manages the hardware resources in order to provide for an orderly and controlled allocation of the processors, memories, and I/ O devices among the various programs competing for them.

What is setup time?

The time spent in loading, unloading, mounting of the programs are called setup time.

Reasons for Development of OS

Problems encountered by earlier computer systems are:

a.       Setup time

When we put each job onto the machine and during which time the computer was completely set up is called setup time. E.g., changing tape reels on tape units, changing stationery on a printer, etc.

b.      Manual intervention

This is necessary in order to investigate error conditions and to initiate corrective action. Again, the computer would lay idle (setup) while this was being done.

c.       The imbalance between the processor and peripherals

This meant that the central processor was lying idle for long periods of time during the operation of peripheral units.

We can view an OS as a resource allocator. Many computers resources are required to solve the problem.

CPU time, IO devices, memory space, file storage space, etc. The OS acts as the manager of these resources and allocates them to specific problems and users as necessary for their tasks, thus maintains the efficiency of the computer.

Another view of an OS is a Control Program. A control program is responsible for the execution of user problems in an efficient and proper way so as to prevent errors and improper use of the computer, especially concerned with the operation and control of IO devices.