Page 11 - iPlus_Ver_2.0_class_8
P. 11

•  Assigning Tasks to the CPU: An Operating system handles the scheduling, synchronization,
                    processing suspension and resumption of processes. Operating system can independently
                    prioritize jobs for processing.

                 •  Managing Memory: It is the process of coordinating and controlling the use of memory in a
                    computer system. It allocates a job to a free memory partition.
                 •  Managing Resources: An operating  system keeps track  of the  hardware  and  software
                    requirements of the processes. It works as a manager of the resources and allocates them to
                    different programs.

                 •  Managing Devices: At  the  time of  execution  of  any  program,  operating  system directly
                    controls the operation of the input-output (I/O) devices like controlling the action of the
                    printer, CD-ROM drives, etc. When we give an instruction to the computer by using an input
                    device, the computer processes the instruction and produces the desired result on the output
                    device.
                 •  Security: An Operating system protects  information and  resources  against  unauthorised
                    access using login and password.


                  i +  TYPES OF OPERATING SYSTEMS

                 There are different types of operating systems. The operating system can be categorised on
                 the basis of control and applications they support. Let us briefly discuss the important types of
                 operating systems.

                 •  Single-user Operating System: A single-user operating system provides access to a single
                    user at a time. The most commonly used single-user operating system is DOS.
                 •  Multi-processing  Operating  System:  In this operating  system, processing is carried
                    independently in more than one location but with sharing of computational capacity. It is
                    accessed by set of computers interconnected by a network. It gives an impression to the user
                    that he is working on a single system. This type of operating system provides higher speed
                    and the capability to run multiple applications at the same time.
                 •  Multi-tasking Operating System: Such operating systems allow the computer to work on
                    more than one application by switching among them. The switching occurs so frequently
                    that the user can interact with each program conveniently. All the tasks share a common
                    processing resource like a CPU. In this type of operating system, the priority of tasks can also
                    be changed according to the requirements. The most commonly used multitasking operating
                    systems are Windows XP, Windows 7, Windows 10, UNIX and Linux.

                 •  Multi-user Operating System: Some operating systems allow access to two or more users
                    to run the same programs at the same time on a network. Some operating systems permit
                    hundreds or even thousands of concurrent users. Examples of multi-user operating systems
                    are Linux, Windows, etc.

                 •  Real-time  Operating  System: It processes instructions  and  produces  a response within
                    a specified time. It is a computing environment that reacts to input within specified time.
                    Example: ATM, traffic signal, etc.




                                                                                                                  9
                                                                                              Operating System
   6   7   8   9   10   11   12   13   14   15   16