All these are metadatas, a term for the descriptive information, which embedded inside an image or other type of digital medias. Metadata is becoming increasingly important in this age of digital where users are looking for a way to store information with their pictures that is portable and stays with the file, both now and into the future.EXIF Exchangeable Image File Format
However, there are other types of metadata that allow users to maintain their own description within a file. This metadata might include the characteristics of the photo, copyright, caption, credits, keywords, creation date and location, source information, or special instructions. Two of the most commonly used metadata formats for image files are IPTC and XMP.
IPTC International Press Telecommunications Council
IPTC is the standard developed in the 1970's by the International Press Telecommunications Council. It was initially developed as a standard for exchanging information between news organizations and has evolved over time. Around 1994, Adobe Photoshop's "File Info" form enabled users to insert and edit IPTC metadata in digital image files and so it was adopted by stock photo agencies, and other publishing businesses outside of the news media.
XMP Extensible Metadata Platform
XMP is the new XML-based "Extensible Metadata Platform" developed by Adobe in 2001. Adobe worked with the IPTC to incorporate the old "IPTC headers" into the new XMP framework and in 2005 the "IPTC Core Schema for XMP" specification was released. XMP is an open-source, public standard, making it easier for developers to adopt the specification in third-party software. XMP metadata can be added to many file types, but for graphic images it is generally stored in JPEG and TIFF files.