Important PointsAn Operating SystemAn operating system is a software program required to manage and operate a computing device like smartphones, tablets, computers, supercomputers, web servers, cars, network towers, smartwatches, etc. It is the operating system that eliminates the need to know coding language to interact with computing devices. It is a layer of graphical user interface (GUI), which acts as a platform between the user and the computer hardware. Moreover, the operating system manages the software side of a computer and controls programs execution. Five of the most common operating systems are Microsoft Windows, Apple macOS, Unix, Linux, Android, and Apple's iOS. Additional InformationOpera: Opera is a multi-platform web browser developed by its namesake company Opera. Opera is a Chromium-based browser. It distinguishes itself from other browsers through its user interface and other features. Hence, Opera is not an Operating System.