GMPG or Global Multimedia Protocols Group is an informal organization who engages in experiments in Metamemetics.
It was first mentioned in 1992 by author Neal Stephenson in his novel Snow Crash.[1]
GMPG was founded by Tantek Çelik, Eric Meyer, and Matthew Mullenweg who developed the initial principles for XFN, the XHTML Friends Network as an attempt for the creation of a simple way to express human relationships on the Web within HTML (machine-readable).
XFN provides a list of non-standard attribute values for the HTML attribute "rel", which is used within the "A" element for hyperlinks.