Types of Operating System
Types of Operating System
OS are classified into the following types depending on their capability of processing
Single User and Single Task OS: It is used on a standalone single computer for performing a single task. Operating systems for Personal Computers (PC) are single-user OS. Single user OS are simple operating system designed to manage one task at a time. MS-DOS is an example of single user OS.
Multiuser OS is used in mini computers or mainframes that allow same data and applications to be accessed by multiple users at the same time. The users can also communicate with each other. Linux and UNIX are examples of multiuser OS.
Multiprocessing OS have two or more processors for a single running process. Processing takes place in parallel and is also called parallel processing. Each processor works on different parts of the same task, or, on two or more different tasks. Since execution takes place in parallel, they are used for high speed execution, and to increase the power of computer. Linux, UNIX and Windows 7 are examples of multiprocessing OS.
Time sharing Operating System: It allows execution of more than one tasks or processes concurrently. For this, the processor time is divided amongst different tasks. This division of time is also called time sharing. The processor switches rapidly between various processes. After the stipulated time is over, the CPU shifts to next task in waiting, So this type of operating system employs round robin scheduling technique. The system switches rapidly from one user to another but still each user feels that it is getting a dedicated CPU time. Virtual Memory techniques are used in this type of operating system. For example, the user can listen to music on the computer while writing an article using a word processing software. The user can switch between the applications and also transfer data between them. Time sharing operating system can be both single user and multiuser. Windows 95 and all later versions of Windows are examples of multitasking OS.
Real Time Operating System: It is a multitasking operating system designed for real time applications like robotics. In this type of operating system, the tasks have to be done within a fixed deadline. System performance is good if task is finished within this deadline. If it is not done, the situation is called Deadline Overrun. Lesser the deadline over run, better is the system efficiency. Hence Real Time operating systems depend not only on the logical result of the computation but also on the time in which the results are produced.
Distributed Operating System: On a network data is stored and processed on multiple locations. The Distributed Operating System is used on networks as it allows shared data/files to be accessed from any machine on the network in a transparent manner. We can insert and remove the data and can even access all the input and output devices. The users feel as if all data is available on their workstation itself.
Interactive Operating System: This is the operating system that provides a Graphic User Interface (GUI) through which the user can easily navigate and interact. The computer responds almost immediately after an instruction has been entered, and the user can enter new instructions after seeing the results of the previous instructions.
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.