An operating system is a powerful, and usually large, program that controls and manages the hardware and other software on a computer. All computers and computer-like devices require operating systems, including your laptop, tablet, desktop, smartphone, smartwatch, and router.

Windows:

The Microsoft Windows operating system is a set of operating systems developed by Microsoft Corporation of the United States. It was introduced in 1985. It was originally a Microsoft-DOS emulation environment. The subsequent system version was not only easy to use due to continuous update and upgrade by Microsoft, but also slowly became The favorite operating system for every household.

Ubuntu：

Ubuntu (Friends, Tuoba, Ubuntu) is an open source GNU/Linux operating system based on desktop applications. Ubuntu is based on Debian GNU/Linux and supports x86, amd64 (x64) and ppc architectures. Created by a global professional development team (Canonical Ltd)