Editing Description logic (section)

===Reasoners===
There are some [[semantic reasoner]]s that deal with OWL and DL. These are some of the most popular:
* [http://lat.inf.tu-dresden.de/systems/cel/ CEL] is an open source LISP-based reasoner (Apache 2.0 License).
* [https://web.archive.org/web/20060419191746/http://www.cerebra.com/ Cerebra Engine] was a commercial C++-based reasoner, acquired in 2006 by webMethods.
* [http://owl.man.ac.uk/factplusplus FaCT++ ] is a free open-source C++-based reasoner.
* [[KAON|KAON2]] is a free (for non-commercial use) Java-based reasoner, offering fast reasoning support for OWL ontologies.
* [http://www.cs.man.ac.uk/~schmidt/mspass/ MSPASS] is a free open-source C reasoner for numerous DL models.
* [https://web.archive.org/web/20070925082014/http://pellet.owldl.com/ Pellet] is a dual-licensed (AGPL and proprietary) commercial, Java-based reasoner.
* [http://www.racer-systems.com/ RacerPro] of Racer Systems was a commercial (free trials and research licenses are available) lisp-based reasoner, today both an open source version of RACER exists from the original developers at Lübeck University using the BSD 3 license, and also a commercialized version, still named [https://franz.com/agraph/racer/racer_features.lhtml RacerPro by Franz Inc.]
* [http://sim-dl.sourceforge.net/ Sim-DL] is a free open-source Java-based reasoner for the language ALCHQ. It also provides a similarity measurement functionality between concepts. To access this functionality a Protégé plugin can be used.
* [http://hermit-reasoner.com/ HermiT] is an [[Open-source model|open-source]] reasoner based on the "hypertableau" calculus. It is developed by the [[University of Oxford]].
* [https://owlready2.readthedocs.io/en/latest/ Owlready2] is a package for ontology-oriented programming in [[Python (programming language)|Python]]. It can load OWL 2.0 ontologies as Python objects, modify them, save them, and perform reasoning via [http://hermit-reasoner.com/ HermiT] (included). Owlready2 allows a transparent access to OWL ontologies (contrary to usual Java-based API).
* [https://github.com/dice-group/owlapy/releases OWLAPY]. OWLAPY is an open-source Python framework for creating, manipulating, and reasoning with OWL ontologies. It includes a built-in StructuralReasoner for efficient, lightweight reasoning and wrappers for well-known Java-based reasoners like HermiT, Pellet, JFact, and Openllet.