The operating systems I know are Microsoft Windows mac OS and Linux in desktop operating systems
Android iOS in mobile operating systems.

Desktop Operating Systems:

1)Microsoft Windows (using)
This is the operating system what i am using now.
And on PCs Windows may be still the most popular operating system.
It is a graphical operating system shell for MS-DOS in response to the growing interest in graphical user interfaces (GUIs).

2)macOS (used)