The thumbnail is part of the EXIF metadata. It's reasonably well-known now, but it was not always the case... http://graphicssoft.about.com/b/2003/07/26/techtv

The thumbnail is part of the EXIF metadata. It's reasonably well-known now, but it was not always the case... http://graphicssoft.about.com/b/2003/07/26/techtvs-cat-schwartz-exposed-is-photoshop-to-blame.htm http://graphicssoft.about.com/b/2003/07/26/techtvs-cat-schwa...