(OS) Operating System

An operating system (OS) is a software program that manages the hardware and software resources of a computer, as well as serving as an interface between the user and the computer. The operating system performs tasks such as controlling the input and output of data, managing system memory and processing, organizing files, and running application programs. Examples of widely used operating systems include Microsoft Windows, Apple's macOS, and Linux-based systems such as Ubuntu and Fedora. Mobile devices also have their own operating systems, such as Google's Android and Apple's iOS.

Here are some links related to operating systems that you may find helpful:

Additionally, you may find the following resources useful for learning more about operating systems:

As of my knowledge cutoff (2021), the most widely used operating system in the world is Microsoft Windows. Windows is installed on the majority of personal computers and laptops, and its various versions (such as Windows 7, Windows 8/8.1, and Windows 10) are used by billions of people globally.

In terms of mobile operating systems, Google's Android is the most popular, with a market share of around 74% as of the fourth quarter of 2020. Apple's iOS, which runs on iPhones and iPads, is the second-most popular mobile operating system with a market share of around 24%.

It's important to note that the popularity of operating systems can vary depending on geographical location and other factors, but these are the general trends as of my knowledge cutoff.