An Operating system is defined as a system software which acts as an interface between a user and the hardware (i.e. all computer resources) it is one of the
The primary goal of an operating system is to make the computer system convenient to use and secondary goal is to use computer hardware in an efficient manner.
An operating system mainly has two parts -> Kernel and shell.
In which the kernel is responsible for interacting with hardware and the shell is responsible for interacting with the user.
Some of the examples of operating systems are: Windows, Linux, Unix, etc.
Types of operating systems (OS):
- Batch Operating System
- Time Sharing Operating System
- Real Time Operating System
a) Batch Operating System :
In batch operating system the users do not interact with the computer directly and there is an operator which takes certain or similar jobs having same requirements and group them into batches or parts. It is the responsibility of operator to store the jobs with similar needs and process it further.
b) Time Sharing Operating System :
In time sharing operating system a technique called time sharing (sharing the time with others) works, which enables many people located at different terminals to use a particular computer system at the same time. The process time which is shared among multiple users symontianisty is term as time sharing.
c) Real Time Operating System :
Real time operating system works very quickly as the time interval required in this OS to process and respond to input is very small and this time interval is called response time. Real time system are used when there are very strict time requirement for example – in missile systems .
Some important functions of operating system are:
1) Process management
2) Memory management
3) File management
1. Process management:
Process management module takes care of creation and deletion of process that occurs while processing of operating system, it works by scheduling of system resources to different processes requesting them and providing mechanism for synchronizing and communication among them.
2. Memory management:
Memory management module takes care of the allocation and deallocation of memory spaces for programs in need of these resources.
3. File management:
File management module takes care of file related activities such as organization storage, naming, sharing, retrieval and protection of files.
Security module works for protecting the resources and information of a computer system against from unauthorised excess.