In
computer science
Computer science is the study of computation, automation, and information. Computer science spans theoretical disciplines (such as algorithms, theory of computation, information theory, and automation) to Applied science, practical discipli ...
and
artificial intelligence
Artificial intelligence (AI) is intelligence—perceiving, synthesizing, and inferring information—demonstrated by machines, as opposed to intelligence displayed by animals and humans. Example tasks in which this is done include speech re ...
, ontology languages are
formal language
In logic, mathematics, computer science, and linguistics, a formal language consists of words whose letters are taken from an alphabet and are well-formed according to a specific set of rules.
The alphabet of a formal language consists of symb ...
s used to construct
ontologies
In computer science and information science, an ontology encompasses a representation, formal naming, and definition of the categories, properties, and relations between the concepts, data, and entities that substantiate one, many, or all domains ...
. They allow the encoding of
knowledge
Knowledge can be defined as awareness of facts or as practical skills, and may also refer to familiarity with objects or situations. Knowledge of facts, also called propositional knowledge, is often defined as true belief that is distinc ...
about specific
domains and often include reasoning rules that support the processing of that knowledge. Ontology languages are usually
declarative language
In computer science, declarative programming is a programming paradigm—a style of building the structure and elements of computer programs—that expresses the logic of a computation without describing its control flow.
Many languages that a ...
s, are almost always generalizations of
frame language Frames are an artificial intelligence data structure used to divide knowledge into substructures by representing " stereotyped situations". They were proposed by Marvin Minsky in his 1974 article "A Framework for Representing Knowledge". Frames are ...
s, and are commonly based on either
first-order logic
First-order logic—also known as predicate logic, quantificational logic, and first-order predicate calculus—is a collection of formal systems used in mathematics, philosophy, linguistics, and computer science. First-order logic uses quantifie ...
or on
description logic.
Classification of ontology languages
Classification by syntax
Traditional syntax ontology languages
*
Common Logic
Common Logic (CL) is a framework for a family of logic languages, based on first-order logic, intended to facilitate the exchange and transmission of knowledge in computer-based systems.
The CL definition permits and encourages the development o ...
- and its dialects
*
CycL
CycL in computer science and artificial intelligence is an ontology language used by Doug Lenat's Cyc artificial intelligence project. Ramanathan V. Guha was instrumental in the design of early versions of the language. There is a close varian ...
*
DOGMA
Dogma is a belief or set of beliefs that is accepted by the members of a group without being questioned or doubted. It may be in the form of an official system of principles or doctrines of a religion, such as Roman Catholicism, Judaism, Islam ...
(Developing Ontology-Grounded Methods and Applications)
*
F-Logic F-logic ( frame logic) is a knowledge representation and ontology language. F-logic combines the advantages of conceptual modeling with object-oriented, frame-based languages and offers a declarative, compact and simple syntax, as well as the wel ...
(Frame Logic)
*
FO-dot (First-order logic extended with types, arithmetic, aggregates and inductive definitions)
*
KIF (Knowledge Interchange Format)
**
Ontolingua based on KIF
*
KL-ONE
KL-ONE (pronounced "kay ell won") is a knowledge representation system in the tradition of semantic networks and frames; that is, it is a frame language. The system is an attempt to overcome semantic indistinctness in semantic network represent ...
* KM programming language
*
LOOM (ontology)
Loom is a knowledge representation language developed by researchers in the artificial intelligence research group at the University of Southern California's Information Sciences Institute. The leader of the Loom project and primary architect fo ...
* OCML (Operational Conceptual Modelling Language)
*
OKBC (
Open Knowledge Base Connectivity)
* PLIB (Parts LIBrary)
*
RACER
Markup ontology languages
These languages use a
markup scheme to encode knowledge, most commonly with
XML
Extensible Markup Language (XML) is a markup language and file format for storing, transmitting, and reconstructing arbitrary data. It defines a set of rules for encoding documents in a format that is both human-readable and machine-readable ...
.
*
DAML+OIL
*
Ontology Inference Layer OIL (Ontology Inference Layer or Ontology Interchange Language) can be regarded as an ontology infrastructure for the Semantic Web. OIL is based on concepts developed in Description Logic (DL) and frame-based systems and is compatible with RDFS ...
(OIL)
*
Web Ontology Language
The Web Ontology Language (OWL) is a family of knowledge representation languages for authoring ontologies. Ontologies are a formal way to describe taxonomies and classification networks, essentially defining the structure of knowledge for vario ...
(OWL)
*
Resource Description Framework The Resource Description Framework (RDF) is a World Wide Web Consortium (W3C) standard originally designed as a data model for metadata. It has come to be used as a general method for description and exchange of graph data. RDF provides a variety of ...
(RDF)
*
RDF Schema
RDF Schema (Resource Description Framework Schema, variously abbreviated as RDFS, , RDF-S, or RDF/S) is a set of classes with certain properties using the RDF extensible knowledge representation data model, providing basic elements for the descr ...
(RDFS)
*
SHOE
A shoe is an item of footwear intended to protect and comfort the human foot. They are often worn with a sock. Shoes are also used as an item of decoration and fashion. The design of shoes has varied enormously through time and from culture t ...
Controlled natural languages
*
Attempto Controlled English
Attempto Controlled English (ACE) is a controlled natural language, i.e. a subset of standard English with a restricted syntax and restricted semantics described by a small set of construction and interpretation rules. It has been under developmen ...
Open vocabulary natural languages
*
Executable English
In computing, executable code, an executable file, or an executable program, sometimes simply referred to as an executable or binary, causes a computer "to perform indicated tasks according to encoded instructions", as opposed to a data file ...
www.executable-english.com
/ref>
Classification by structure (logic type)
Frame-based
Three languages are completely or partially frame-based languages.
* F-Logic F-logic ( frame logic) is a knowledge representation and ontology language. F-logic combines the advantages of conceptual modeling with object-oriented, frame-based languages and offers a declarative, compact and simple syntax, as well as the wel ...
* OKBC
* KM
Description logic-based
Description logic provides an extension of frame language Frames are an artificial intelligence data structure used to divide knowledge into substructures by representing " stereotyped situations". They were proposed by Marvin Minsky in his 1974 article "A Framework for Representing Knowledge". Frames are ...
s, without going so far as to take the leap to first-order logic
First-order logic—also known as predicate logic, quantificational logic, and first-order predicate calculus—is a collection of formal systems used in mathematics, philosophy, linguistics, and computer science. First-order logic uses quantifie ...
and support for arbitrary predicates.
* KL-ONE
KL-ONE (pronounced "kay ell won") is a knowledge representation system in the tradition of semantic networks and frames; that is, it is a frame language. The system is an attempt to overcome semantic indistinctness in semantic network represent ...
* RACER
* OWL
Owls are birds from the order Strigiformes (), which includes over 200 species of mostly solitary and nocturnal birds of prey typified by an upright stance, a large, broad head, binocular vision, binaural hearing, sharp talons, and feathers a ...
.
Gellish
Gellish is an ontology language for data storage and communication, designed and developed by Andries van Renssen since mid-1990s. It started out as an engineering modeling language ("Generic Engineering Language", giving it the name, "Gellish") bu ...
is an example of a combined ontology language and ontology that is description logic based. It distinguishes between the semantic differences among others of:
* relation types for relations between concepts (classes)
* relation types for relations between individuals
* relation types for relations between individuals and classes
It also contains constructs to express queries and communicative intent.
First-order logic-based
Several ontology languages support expressions in first-order logic
First-order logic—also known as predicate logic, quantificational logic, and first-order predicate calculus—is a collection of formal systems used in mathematics, philosophy, linguistics, and computer science. First-order logic uses quantifie ...
and allow general predicates.
* Common Logic
Common Logic (CL) is a framework for a family of logic languages, based on first-order logic, intended to facilitate the exchange and transmission of knowledge in computer-based systems.
The CL definition permits and encourages the development o ...
* CycL
CycL in computer science and artificial intelligence is an ontology language used by Doug Lenat's Cyc artificial intelligence project. Ramanathan V. Guha was instrumental in the design of early versions of the language. There is a close varian ...
* FO-dot (First-order logic extended with types, arithmetic, aggregates and inductive definitions)
* KIF
See also
* Domain theory
Domain theory is a branch of mathematics that studies special kinds of partially ordered sets (posets) commonly called domains. Consequently, domain theory can be considered as a branch of order theory. The field has major applications in computer ...
* Formal concept analysis
* Galois connection
* Lattice (order)
A lattice is an abstract structure studied in the mathematical subdisciplines of order theory and abstract algebra. It consists of a partially ordered set in which every pair of elements has a unique supremum (also called a least upper bou ...
* List of knowledge representation languages
* Modeling language
A modeling language is any artificial language that can be used to express information or knowledge or systems in a structure that is defined by a consistent set of rules. The rules are used for interpretation of the meaning of components in th ...
* OntoUML
OntoUML is an ontologically well-founded language for Ontology-driven Conceptual Modeling. OntoUML is built as a UML extension based on the Unified Foundational Ontology (UFO). The foundations of UFO and OntoUML can be traced back to Giancarlo ...
Notes
References
* Oscar Corcho, Asuncion Gomez-Perez,
A Roadmap to Ontology Specification Languages
' (2000)
''Introduction to Description Logics'' – DL course
by Enrico Franconi, Faculty of Computer Science, Free University of Bolzano, Italy
{{Non-classical logic
Modeling languages