Files with the extension .swf are Macromedia Flash files (http://macromedia.com). They are Courtesy of The Red Road (http://www.sci.fi/~leo/). I have included them as I am a graphics 'nut' and I really believe they help a lot of text challenged people, myself included, understand several basic concepts.
I develop on a Macintosh. Work is checked for compatibility
on a Compaq PC running Windows 2000 and Office 2000. The free download
version of Quicktime (http://www.apple.com/quicktime/) plays .swf files on
both my Compaq peecee and on my Macintosh.
Both computers have Shockwave and the Flash player installed, as well as the latest Quicktime. All are free downloads. There is a Quicktime Pro edition for sale, but you only need the free downloadable version.
On the Macintosh platform, the files 'play' in Powerpoint like movies when in the SlideShow mode. On the PeeCee platform they do not. The Macintosh version of Powerpoint handles .swf files as 'movies' while the PeeCee does not appear to.