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The page can be viewed 3 ways, Visual, Text or Page Builder. Visual Editor is the default and is similar to Word. Text is the code view.
And Page Builder is used to layout your page. 
If the page was converted to Page Builder, you there would only see; be Revert to Editor tab.
| Warning |
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If you click on Revert to Editor, you will lose the Page Builder layout and any of the widgets that were setup. |
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