The new design in Microsoft Office 2010 that includes the File tab replacing the Microsoft Office Button
included in the 2007 Microsoft Office system release in the following programs: Word, Excel, PowerPoint, Access, and Outlook (in the composing and reading windows).
The button and the tab replace the File menu that was in some 2007 Microsoft Office system programs and in Microsoft Office 2003 and earlier.
The Microsoft Office Button and the File tab are in the same general location but look different.
When you click the File tab, you see the same basic commands that were available after you click the Microsoft Office Button
or on the File menu in some 2007 Microsoft Office system programs and in Microsoft Office 2003 and earlier. These basic commands include, but are not limited to, Open, Save, and Print. Some commands, such as Import, have been moved to the ribbon.
For more information about the File tab, see What and where is the Backstage view?