MCF was developed by Ramanathan V. Guha at Apple Computer's Advanced Technology Group between 1995 and 1997.
Rooted in knowledge-representation systems such as CycL, KRL, and KIF, it sought to describe objects, their attributes, and the relationships between them.
It generated a 3D visualization of a web site's table of contents, based on MCF descriptions.
[1] When the research project was discontinued, Guha left Apple for Netscape, where, in collaboration with Tim Bray, he adapted MCF to use XML[2][3] and created the first version of the Resource Description Framework (RDF).
Each value can be a reference to another entity (via its identifier), a string (enclosed by double quotes) or a number.