A family of Microsoft presentation graphics products that offer tools for creating presentations and adding graphic effects like multimedia objects and special effects with text.
MS doesn't bother to create user manuals any more. They stopped doing printed manuals in the 1990's. "Too expensive" for M$ to keep them up to date. MS depends on independent authors and publisher to create books.
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MS does provide some support web pages for their various applications.
https://support.microsoft.com/en-us/powerpoint
https://support.microsoft.com/en-us/office/powerpoint-help-5395bb85-eb6f-47fa-b5af-52996bac819e
John has pointed you to a good list of resources. There are lots more, including free training, you just have to try various search criteria.
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A key point about these online resources, don't ignore them just because they are not for your specific version of Office / PPT. The fundamental, core, features of the Office apps have been in place since the 1990's. Each new version / release added just a few new features. You could even use manuals and training for the "Menu" user interface versions, 2003 and earlier, if you are willing to be a little flexible. The fundamentals they cover there still apply in the ribbon versions. Often the commands still have the same names. Actually, the underlying command names are often based on the old menu, ie "EditCopy" is the copy command which was formerly located on the Edit menu. It doesn't make sense in the context of the Ribbon "gooey" (GUI) but made perfect sense when we still used the menu UI.
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