JFIF

from The Free On-line Dictionary of Computing (8 July 2008)

JPEG File Interchange Format
JFIF

   <graphics, file format> (JFIF) The technical name for the file
   format better known as {JPEG}.  This term is used only when
   the difference between the JPEG file format and the JPEG image
   {compression} {algorithm} is crucial.

   (1998-02-10)