To hide the ribbon, on any one of the tabs of the ribbon.

The ribbon is a set of toolbars at the top of the window in Office programs designed to help you quickly find the commands that you need to complete a task. Sometimes the ribbon can get hidden and it's hard to find. The quickest way to show the ribbon is to click on any visible tab, like Home, Insert or Design. You might also want to hide the ribbon to maximize screen space.

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