Nothing -- neither is embedded.

You can embed WAV files.

You can add RIFF-WAV headers to MP3s to fool PPT into thinking the MP3 is a
WAV so it can be embedded. You need a utility like Cdex to do that, and if
you need the sound to play on all systems, I wouldn't recommend this because
there have been reports of these sound files (MP3s with RIFF-WAV headers)
not playing on all machines.

Neophyte questions are fine. That's what we're here for. :-)

Jim,

Strictly speaking

.wav files are the only thing that can be embedded (included) within your
powerpoint file.

.mp3 files are a lot smaller- you can fool powerpoint into thinking they are
.wav files
see
http://www.technologytrish.co.uk/pptembedmp3.html

.wma files are microsofts answer to mp3 files, in that they are smaller than
regular .wav files.
but they can include some kind of 'protection' to stop people copying them -
were as an mp3 has no limits

Cheers
TAJ Simmons
microsoft powerpoint mvp

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