The actual format is the same since PowerPoint 97 so you can open a
presentation created in PowerPoint 2000, 2002, 2003 (Windows) and 98, 2001,
X, 2004 (Mac) in PowerPoint 97 for Windows.
However, password protected presentations (available since PowerPoint 2002)
cannot be opened in older versions.
Also, new features like animated GIFs, picture bullets (PowerPoint 2000),
new animations and transitions (PowerPoint 2002) and music playlists
(PowerPoint 2003) will not work in the older version.
If you want to see all those features, download the free PowerPoint 2003
Viewer:
PowerPoint Viewer 2003 for Windows -
http://snipurl.com/ppview2003
In all cases, you'll also not be able to see QuickTime movies inserted in
the Mac versions.
--
Geetesh Bajaj, Microsoft PowerPoint MVP
PowerPoint Notes:
http://www.indezine.com/notes
Free Templates:
http://www.indezine.com/powerpoint/templates/freetemplates.html
Technical Specialist, PowerPoint Live
http://www.powerpointlive.com