PDF slideshows are a very good way to share photographic presentations. They can be used even if your audience uses a Macintosh or Linux computer. Unlike "self-launching" presentations, this is a safe format – no program code is transferred, and thus the risk of transferring viruses among computers is minimal.
At their core, PDF slideshows are standard PDF files that contain one full-page photograph per page. During slideshow generation, you can set the way each photo (page) in the slideshow will be displayed. This means the Transition effect used and the amount of time to Show (the) image for – these can be set individually for each picture. Click Apply to All to apply the selected effect and display time to all pictures. You can also give the whole document a unified effect display time (Show effect for) and you can set a soundtrack. The soundtrack can be in the MP3, WAV, MIDI, AIFF or AU format. When possible, use MP3, because of its advanced compression.
For your audience to see your slideshow as intended, they need to have Adobe Reader 6 or higher on their computer. (It is unlikely that they will not.) Older versions of Adobe Reader and other PDF viewers (e.g. GSView) will display the photos only, without the transition effects and the soundtrack.