There's one point Glenn forgot to mention: GIF files support multiple "frames," which means they can be used for simple animation. I believe this feature is exclusive to GIF since, until Netscape supported it, no one had bothered with this rather obscure part of the GIF specification. PNG was designed before Netscape supported multi-frame GIFs, and the designers didn't see the point of supporting this completely unused feature. Pity.
Just Show Me the Pictures!
Do you ever find that you don't have time to read those long email missives from Aunt Carol, but really do want to see the photos that she has lovingly attached? In Apple Mail, click the Quick Look button located in the message header. You'll get an easily browsed view of just the attached photos, and you can even add them to iPhoto, if you like!
better-looking. Edit your PDFs anywhere. Sign contracts, make
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Syncs via iCloud and Dropbox. <http://smle.us/tbpdfpen-ipad>