Versions of the SUO IFF

• 7 July 2001
  This is the starter document, and is also known as the IFF Foundation Ontology. It served as a prototype for the SUO IFF.
• 4 October 2001
  The Upper Core, Category Theory and Upper Classification meta-ontologies were introduced into the SUO IFF upper metalevel.
• 5 December 2001
  The Top Core meta-ontology was introduced into the SUO IFF top metalevel. The Upper Core meta-ontology was revised. The Category Theory and Upper Classification meta-ontologies are the same as in the 4 October 2001 version of the SUO IFF.
• 2 January 2002
  The Top Core, Upper Core, Category Theory and Classification meta-ontologies were revised.
• 15 May 2002
  The Model Theory meta-ontology was introduced into the SUO IFF lower metalevel. The other meta-ontologies are the same as in the 2 January 2002 version of the SUO IFF.
• 5 December 2002
  The Ontology meta-ontology was introduced into the SUO IFF lower metalevel. The other meta-ontologies are the same as in the 15 May 2002 version of the SUO IFF.