The Meta-Object Facility (MOF) is an Object Management Group

Object Management Group

Object Management Group is a consortium, originally aimed at setting standards for distributed object-oriented systems, and is now focused on modeling and model-based standards.- Overview :...

 (OMG) standard for model-driven engineering

Model-driven engineering

Model-driven engineering is a software development methodology which focuses on creating and exploiting domain models , rather than on the computing concepts...

. The official reference page may be found at OMG's website.
MOF originated in the Unified Modeling Language

Unified Modeling Language

Unified Modeling Language is a standardized general-purpose modeling language in the field of object-oriented software engineering. The standard is managed, and was created, by the Object Management Group...

 (UML); the OMG was in need of a metamodeling

Metamodeling

Metamodeling, or meta-modeling in software engineering and systems engineering among other disciplines, is the analysis, construction and development of the frames, rules, constraints, models and theories applicable and useful for modeling a predefined class of problems...

 architecture to define the UML. MOF is designed as a four-layered architecture. It provides a meta-meta model at the top layer, called the M3 layer. This M3-model is the language used by MOF to build metamodels, called M2-models.