Operating System
An operating system is a software that manages computer hardware. The hardware must An operating An operating system acts as an intermediary between the user of a computer and computer hardware. The purpose of an operating system is to provide an environment in which a An operating system acts as an intermediary between the user of a computer and computer hardware. The purpose of an operating system is to provide an environment in which a user can execute programs conveniently and efficiently.
- 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 application 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, a memory management module, I/O programs, and a file system.
Features of Operating system – Operating system has the following features:
Convenience: An OS makes a computer more convenient to use.
- Efficiency: An OS allows the computer system resources to be used efficiently.
- Ability to Evolve: An OS should be constructed in such a way as to permit the effective development, testing, and introduction of new system functions at the same time without interfering with service.
- Throughput: An OS should be constructed so that It can give maximum throughput(Number of tasks per unit time).
Major Functionalities of Operating System:
- Resource Management: When parallel accessing happens in the OS means when multiple users are accessing the system the OS works as Resource Manager, Its responsibility is to provide hardware to the user. It decreases the load in the system.
- Process Management: It includes various tasks like scheduling and termination of the process. It is done with the help of CPU Scheduling algorithms.
- Storage Management: The file system mechanism used for the management of the storage. NIFS, CFS, CIFS, NFS, etc. are some file systems. All the data is stored in various tracks of Hard disks that are all managed by the storage manager. It included Hard Disk.
- Memory Management: Refers to the management of primary memory. The operating system has to keep track of how much memory has been used and by whom. It has to decide which process needs memory space and how much. OS also has to allocate and deallocate the memory space.
- Security/Privacy Management: Privacy is also provided by the Operating system by means of passwords so that unauthorized applications can’t access programs or data. For example, Windows uses Kerberos authentication to prevent unauthorized access to data.The process operating system as User Interface:
- User
- System and application programs
- Operating system
- Hardware