“An Operating system is a program that controls the execution of application programs and acts as an interface between the user of a computer and the computer hardware.”
A more common definition is that the operating system is the one program running at all times on the computer (usually called the kernel), with all else being applications programs.
An Operating system is concerned with the allocation of resources and services, such as memory, processors, devices and information. The Operating System correspondingly includes programs to manage these resources, such as a traffic controller, a scheduler, memory management module, I/O programs, and a file system.
Some of the popular operating systems used in personal computers are DOS, Windows,Unix, Linux, Solaris, etc.
Need for an Operating System
Operating system provides a platform, on top of which, other programs, called application programs can run. As discussed before, it acts as an interface between the computer and the user. It is designed in such a manner that it operates, controls and executes various applications on the computer. It also allows the computer to manage its own resources such as memory, monitor, keyboard, printer etc.
Our choice of operating system, therefore, depends to a great extent on the CPU and the other attached devices and the applications we want to run. The operating system controls the various system hardware and software resources and allocates them to the users or programs as per their requirement.
Qus. What are various categories of software?
Ans: Software are classified into following categories –
(i) System Software
a. Operating System
b. Language Processor
(ii) Application Software
c. Customized software
d. Developer Tools
Qus. What is the difference between an interpreter and a compiler?
Interpreter: Interpreter is a type of system software that translates and executes instructions written in a computer program lini-by-line, unit by unit etc. It is slower in execution because each time when you run the program translation is required.
Compiler: Compiler is another type of system software that translates and executes instructions written in a computer program in one go. Once compiled program need not to translate again so it works faster.
Qus. What is application software? Why it is required?
Ans: Application software is the set of programs necessary to carry out operations for a specific task. Such as for word processing there are many application software like MS-Word, Wordpad etc. These software are required to perform special task using the computer like painting, recording, typing, data handling etc.
Qus. What is system software?
Ans: The software that controls internal computer operations is called system software. It manages all the resources of a system. Its example is Operating System.
Qus. Discuss the role of utility software in the context of computer performance?
Ans: Utilities are those application programs that assist the computer by performing housekeeping functions like backing up disk or scanning/cleaning viruses or arranging information etc. its example is Antivirus software.
Qus. What is the importance of an OS?
Ans: An operating system is a program which acts as an interface between a user and the hardware. It manages all the resources of the computer system. It provides and environment to the user to work with. All the application are installed after the operating system is installed. It manages memory, processing, storage, memory etc.
Qus. What is the utility of these software?
(a) disk fragmentor (b) backup software
(a) disk fragmentor: A file is fragmented when it becomes too large for your computer to store in a single location on a disk. When this happens, your computer splits the file up and stores in pieces. You can use fragmented files, but it takes your computer longer to access them.
(b) Backup software: This utility program facilitates the backing-up of disk. Back-up means duplicating the disk information so that in case of any damage or data-loss, this backed-up data may be used.
Qus. Describe the role of Operating System as a resource Manager.
Ans: A computer system has many resources (hardware and software), which may be require to complete a task. The commonly required resources are input/output devices, memory, file storage space, CPU etc. The operating system acts as a manager of the above resources and allocates them to specific programs and users, whenever necessary to perform a particular task. Therefore operating system is the resource manager i.e. it can manage the resource of a computer system internally. The resources are processor, memory, files, and I/O devices. In simple terms, an operating system is the interface between the user and the machine.
Operating System Management Tasks
1. Processor management which involves putting the tasks into order and pairing them into manageable size before they go to the CPU.
2. Memory management which coordinates data to and from RAM (random-access memory) and determines the necessity for virtual memory.
3. Device management which provides interface between connected devices.
4. Storage management which directs permanent data storage.
5. Application which allows standard communication between software and your computer.
6. User interface which allows you to communicate with your computer.
Qus. What are the advantages of parallel computing?
Ans: Parallel computing is a type of computation in which many calculations or the execution of processes are carried out simultaneously. Large problems can often be divided into smaller ones, which can then be solved at the same time. It refers to the simultaneous working of multiple processors to solve a computational problem. Its advantages are –
(i) It saves time and the cost too.
(ii) It makes easier to solve larger or complex problems.
(iii) It provides efficient use of underlying hardware.
(iv) It can utilize the resources available remotely.