What is an operating system? List the typical function of operating system.
An operating system is system software that provides interface between user and hardware. The OS provides the means for the proper use of resources (CPU, memory, I/O devices, data and so on) in the operation of the computer system. An operating system provides an environment within which other programs can also do useful work.
The operating system must fulfill the two main objectives:
- interact with the hardware components, servicing all low- level programmable elements included in the hardware platform
- provide an execution environment to the applications that run on the computer system.
Typical functions of operating system are as follows:
- Process management: During the process execution, it requires certain system resources such as processor, time, main memory, files, etc. Operating system supports multiple processes simultaneously. The process management module of the operating system take care of the creation and termination of the processes, assigning resources to the processes, scheduling processor time to different processes and communication among processes.
- Memory Management module: It takes care of the allocation and deallocation of the main memory to the various processes.
- I/O management: It controls all I/O devices, keeps track of I/O request, issues commands to these devices.
- File management: Data is stored in a computer system as files. The management module takes care of creation, organization, storage, naming, sharing, backup and protection of different files.
- Scheduling: It determines and maintains the order in which the jobs are to be executed by the computer system. This is so because the most important job must be executed first followed by less important jobs.
- Security management: This module of the operating system ensures data security and integrity. It keeps different programs and data which are executing concurrently in the memory in such a manner that they do not interfere with each other.
- Processor management: Operating system assigns processor to the different task that must be performed by the computer system.