An Operating System is an interface between a computer user and computer hardware.
An OS is software which performs all the basic tasks like File Management, Memory Management, Process Management, Handling Input and Output and Controlling Peripheral Devices such as disk drives and printers.
Different Services provided by Operating System
- An Operating system provides an environment for execution of programs.
- It provides certain services to programs and to the users of those programs.
- OS provides varies types of services to users and make easier use of computer.
Types of services are following.
- PROGRAM EXECUTION:-
The system must be able o load a program into memory and run it. The program must be able to complete its execution either normally or abnormally with indicating the errors.
- I/O OPERATION:-
System running program may require I/O. This I/O involves a file or an I/O device. The operating system provide mean to do. Also it manages all I/O operation.
- FILE SYSTEM MANIPULATION:-
Operating system maintains the file system file system do and manages all types of operation doing on the file like: creating, writing, reading, appending, truncating.
Some time process need to exchange the information with another process.
If both process are on same computer than communication will be done by shared memory. If both processes are on different computer in a network, then message passing technique is used. Message is a packet of information.
- ERROR DETECTION:-
The operating system constantly needs to be aware of possible errors. Errors may come in CPU, in memory or in any hardware or any I/O devices. And also error may come in user programs.
For each type of error operating system should take appropriate action. Operating system will detect the errors and give to the users. Operating system will not solve or remove any error.
- RESOURCE ALLOCATION:-
Operating system manage all resources of computer system like CPU cycles memory and file storage. These resources are allocated to the multiple users as per the requirement of users.
- ACCOUNTING :-
Operating system will keep record of which users use how much and what kind of resources.
- PROTECTION :-
Operating system provide security mechanism to protect the system from access of unauthorized users. By given the username and password to the system.