1, OS is an abbreviation for Operating System, translated as "operating system", is the management and control of computer hardware and software resources of the computer program, is running directly on the "bare metal" on the most basic system software, any other software must be supported by the operating system in order to run. Any other software must run under the support of the operating system.
2. Examples of operating systems
Mobile phone field: Android, iOS
Personal computer field: Windows, Mac OS, Linux (Department)
Router: OpenWRT, VxWorks, Linux (customized)
This is the first time that a computer has been used for a long time.