Final answer:
The Show Desktop button is used to minimize all open windows on a Windows operating system, providing quick access to the desktop. Clicking it again will restore the minimized windows.
Step-by-step explanation:
To minimize all windows and view the desktop in a Windows operating system, you can click the Show Desktop button. This button is typically located at the far right end of the taskbar or next to the Start menu on some versions of Windows. When you click this button, all open windows will be minimized, allowing you to access files, folders, or shortcuts on your desktop easily. To restore the minimized windows, you can click the Show Desktop button again.