The operating system (OS) is the most important software that runs on a computer. It manages the memory and processes of the computer, as well as all software and hardware. It also allows communication with the computer. Without an operating system, a computer is useless. Usually several different computer programmes run simultaneously and they all need to access the CPU, RAM, and hard disk of the computer. The operating system coordinates all of these to ensure that each programme gets what it needs.
The operating systems are usually pre-installed on each computer. Most people use the operating system that comes with their computer, but it is possible to update or even switch operating systems. The three most common operating systems for desktop computers and laptops are Microsoft Windows, macOS and Linux. For tablets and smartphones, the most common OS are Android and iOS modern operating systems that use a graphical user interface (GUI). A GUI allows clicking with the mouse on icons, buttons and menus, and everything is clearly represented on the screen by a combination of graphics and text.
The user interface of each operating system has a different look and feel, so switching to a different operating system may seem unfamiliar at first.
Modern operating systems are designed to be easy to use, and most basic principles are the same.
Picture 17: User Interfaces - Operating Systems
An application (app) is a type of software that allows performing specific tasks. When an app is opened, it runs within the operating system until it is closed. Multiple apps can be open at the same time. There are countless desktop apps or programmes. Some are more extensive (i.e. Microsoft Word), while others can only do one or two things (i.e. a clock or a calendar application). Desktop and laptop computers aren't the only devices that can run apps or programmes. Apps for mobile devices such as smartphones and tablets can also be downloaded.
Picture 18: various apps
1. Can you explain the difference between operation software and application software?
2. Can you name the most common operating systems for desktop PCs?