It is for viewing Powerpoint presentations. If someone does not have Powerpoint, they can use it to view presentations. It cannot be used to create or edit presentations. That can only be done with Powerpoint.
what are the four principles for creating effective text presentations in Microsoft PowerPoint
There's no such thing as an "XP PowerPoint." Microsoft PowerPoint is compatible with presentations made in previous versions, including versions that may run on XP but not on Vista (like 97 or 2000).
OpenOffice or LibreOffice can open PowerPoint presentations.
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Microsoft Office for Macs includes PowerPoint for the creation of a presentations. Microsoft also provide a viewer with which Mac users can view PowerPoint presentations without owning PowerPoint itself. Apple's own KeyNote software can save presentations as a PowerPoint file.
maybe try a trivia PowerPoint on a movie or book.
Yes. PowerPoint 2007 (and 2010) support loading presentations that were made in older PowerPoint version.
Copy and paste
slides shows
Yes, of course.
yes