What is Operating System

Definition

An OS is an interface between a person and hardware and controls the execution of all types of programs. An OS is a software that performs all the essential tasks like file management, memory management, process management, handling input and output, and controlling peripheral devices like disk drives and printers.
Some popular OS includes Linux Operating System, Windows Operating System, etc.

Following are a number of important functions of an OS:

Types of OS:

Batch operating system:

The users of a batch OS don’t interact with the computer directly. Each user prepares his job on an off-line device like punch cards and submits it to the computer operator. To hurry up processing, jobs with similar needs are batched together and run as a group.

Time-sharing operating system:

Time-sharing may be a technique that enables many of us, located at various terminals, to use a specific computing system at an equivalent time. Time-sharing or multitasking is a logical extension of multiprogramming. Processor’s time which is shared among multiple users simultaneously is termed time-sharing.

Distributed operating system:

Distributed systems use multiple central processors to serve multiple real-time applications and multiple users. Processing jobs are distributed among the processors accordingly.

Network operating system:

A Network OS runs on a server and provides the server the potential to manage data, users, groups, security, applications, and other networking functions. The first purpose of the network OS is to permit shared file and printer access among multiple computers during a network, typically an area network (LAN), a personal network, or to other networks.

Real-time operating system:

A real-time system is defined as a data processing system during which the interval required to process and answer inputs is so small that it controls the environment. The time taken by the system to reply to an input and display of required updated information is termed as response time. So during this method, the reaction time is extremely less as compared to online processing.

Important Activities:
Security:

By means of password and similar other techniques, it prevents unauthorized access to programs and data.

Job accounting:

Keeping track of your time and resources employed by various jobs and users.

Error detecting aids:

Production of dumps, traces, error messages, and other debugging and error detecting aids.

Control over system performance:

Recording delays between a request for a service and response from the system.