An operating system (OS) is software that manages computer hardware and software resources and provides common services for computer programs. Acting as an intermediary between users and the computer hardware, an operating system enables users to perform tasks such as running applications, managing files, and controlling hardware devices. It facilitates multitasking, resource allocation, file management, and user interface functionalities. Common examples of operating systems include Microsoft Windows, macOS, Linux, and Android. An OS is essential for the operation of computers and mobile devices, providing a stable environment for applications to run while managing the underlying hardware efficiently.