On several image specific properties, there is a large overlap between the tags defined in the TIFF, Exif, TIFF/EP, and DCF standards.

For descriptive metadata, there is an overlap between Exif, IPTC Information Interchange Model and XMP info, which also can be embedded in a JPEG file.

As of 2014[update], many cameras and mobile phones have a built-in GPS receiver that stores the location information in the Exif header when a picture is taken.

Photo-sharing communities like Panoramio, locr or Flickr equally allow their users to upload geocoded pictures or to add geolocation information online.

For example, a photo taken with a GPS-enabled camera can reveal the exact location and time it was taken, and the unique ID number of the device - this is all done by default - often without the user's knowledge.

For example, a whistleblower, journalist or political dissident relying on the protection of anonymity to allow them to report malfeasance by a corporate entity, criminal, or government may therefore find their safety compromised by this default data collection.

In December 2012, anti-virus businessman John McAfee was arrested in Guatemala while fleeing from alleged persecution[22] in neighboring Belize.

[26] According to documents leaked by Edward Snowden, the NSA is targeting Exif information under the XKeyscore program.

[28] Metadata Working Group was formed by a consortium of companies in 2006 (according to their web page) or 2007 (as stated in their own press release).

Version 2.0 of the specification was released in November 2010,[8] giving recommendations concerning the use of Exif, IPTC and XMP metadata in images.

Authorship and copyright information is generally not provided in the camera's output, so it must be filled in during later stages of processing.

This confusion is exacerbated for the subsecond tags, where the granularity (down to 1/10000th of a second in the examples in the standard) is shorter than many common exposure durations.

They are formatted as seven ASCII characters (including the null terminator) denoting the hours and minutes of the offset, like +01:00 or -01:00.

The Exif specification also includes a description of FPXR (FlashPix-ready) information, which may be stored in APP2 of JPEG images using a structure similar to that of a FlashPix file.

In some cases, camera vendors also store important information only in proprietary makernote fields, instead of using available Exif standard tags.