interesting image question

i was wondering what are the origins of the "png" format ... and also why in the world it won't open in windows or mac standard app. (besides photoshop)

PNG stands for portable network graphics and they're a free replacement for GIF's because Unisys started enforcing licensing policies. They look just as good as GIF's and are generally smaller. IE doesn't handle the transparency quite right, but most other browsers do.

Edit: An interesting (though one-sided) discussion can be found here:
www.burnallgifs.org