The Protégé Ontology Editor and Knowledge Acquisition System

Protégé is a free, open source ontology editor and knowledge-base framework.

The Protégé platform supports two main ways of modeling ontologies via the Protégé-Frames and Protégé-OWL editors. Protégé ontologies can be exported into a variety of formats including RDF(S), OWL, and XML Schema. (more)

Protégé is based on Java, is extensible, and provides a plug-and-play environment that makes it a flexible base for rapid prototyping and application development. (more)

Protégé is supported by a strong community of developers and academic, government and corporate users, who are using Protégé for knowledge solutions in areas as diverse as biomedicine, intelligence gathering, and corporate modeling.

community
Registered Users	100,848
protege-users list members	17,230
protege-discussion list members	3,610
protege-owl list members	1,952

Protégé is available from this site as a free download along with plug-ins and ontologies.

downloads
Protégé 3.3.1	August 24th, 2007
Protégé 3.4 beta	June 24, 2008
Protégé 4.0 alpha	June 12, 2008

Protégé is a national resource for biomedical ontologies and knowledge bases supported by the National Library of Medicine
Protégé is a core component of The National Center for Biomedical Ontology
Copyright © 2008 Stanford Center for Biomedical Informatics Research