Operating System

The most important software running on a computer is the operating system. It manages the memory and processes of the computer, as well as all software and hardware. It also enables communication with the computer without needing to know its language. 

Applications use the operating system by requesting services through a defined application programming interface (API). Users can directly interact with the operating system through a user interface (UI). Without an operating system, a computer is essentially useless.

What does an operating system do?

When we look at all the tasks an operating system performs, there are three essential main tasks: it provides a user interface (via a CLI or GUI), launches and manages applications (application management), and makes hardware available to apps (device management).

The User Interface

To be able to communicate with your computer, it needs a user interface. The user interface allows users to configure and troubleshoot the underlying hardware within an operating system. 

The two main types of UI are CLI and GUI.

CLI – Command Line Interface

Through the CLI, users communicate with a system or application by typing in text. This text can consist of commands and parameters related to specific tasks. The system responds to the text, and the user can then type on the next command line that appears. 

Through this interaction of command and response, the user can give a series of commands that are executed by the system or program. 

Advanced users and system administrators primarily use the CLI. 

GUI – Graphical User Interface

The GUI provides a visual interface based on icons and symbols where users can perform computer tasks through human actions. Hardware such as touchpads/trackpads, touchscreens, and mice are needed for these actions.  

Almost every user uses the GUI. 

Application Management

An operating system handles the launching and management of every application. Examples of tasks that fall under this include sharing multiple processes/threads, freeing up enough memory without obstructing other processes, and appropriately detecting and handling error messages. Other tasks include:

• Determining the order in which applications should run.

• Processing input/output (I/O) to and from connected hardware devices.

• Assigning tasks to external devices. 

Device Management

An operating system is responsible for identifying, configuring, and providing overall access to applications for the underlying computer hardware. This allows you, for example, to use your mouse and keyboard. 

Types of Operating Systems

All systems are identical, but different systems serve different hardware and user needs.

General

A general operating system is intended to run different applications on various hardware so users can run one or more applications or tasks simultaneously.

Mobile

Mobile operating systems, such as iOS and Android, are designed to meet the unique needs of mobile devices such as smartphones and tablets. These operating systems emphasise efficient performance, user responsiveness, and attention to data processing tasks.

Embedded

An embedded operating system performs only one major task, so the operating system is stripped down and focused on performance and resilience. The OS must run quickly, not crash, and handle all errors neatly to continue working under all circumstances. The operating system is usually supplied on a chip built into the device itself.

Examples of Operating Systems

Below are some examples of operating systems:

• Windows, macOS and Linux are examples of general-purpose operating systems.

• iOS and Android are examples of mobile operating systems. 

• ATMs and aircraft systems contain embedded operating systems.