MediaWiki:Exif-jpeginterchangeformat/qqq

Exif is a format for storing metadata in image files. See this Wikipedia article and the example at the bottom of this page on Commons. The tags are explained briefly, in further detail here (broken former link, formerly on the Kodak website for Exif v2), now replaced by this PDF (CP-3451 standard for Exif v2.2, sponsored by JEITA, Japan Electronics and Information Technology Industries Association).