image file format
supports storing some Meta Data right inside the image file.
EXIF is one category of Meta Data (some Structured Data inserted by Digital Camera-s), but I'm pretty sure it's different from the basic "comment" bytes (it may even be stored within the "comment" field)
Greg Elin's FotoNotes proposed standard - http://www.fotonotes.net/index.php?action=learnmore#developers
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