TaxonomyTaxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. Among other things, a taxonomy can be used to organize and index knowledge (stored as documents, articles, videos, etc.), such as in the form of a library classification system, or a search engine taxonomy, so that users can more easily find the information they are searching for.
Is-aAn is-a relationship is when one type of object 'is a' instance of another type of object. For example, a cat 'is a' animal, but not vice versa. All cats are animals, but not all animals are cats. The concept becomes important in object oriented programing, where 'is a' relationships are often used as a way to structure code - behaviour that are is relevant to all animals is defined on an animal class, whereas behaviour that is relevant only for cats is defined in a cat class.
Hyponymy and hypernymyHyponymy and hypernymy are semantic relations between a term belonging in a set that is defined by another term and the latter. In other words, the relationship of a subtype (hyponym) and the supertype (also called umbrella term, blanket term, or hypernym). The semantic field of the hyponym is included within that of the hypernym. For example, pigeon, crow, and eagle are all hyponyms of bird, their hypernym. In linguistics, semantics, general semantics, and ontologies, hyponymy () shows the relationship between a generic term (hypernym) and a specific instance of it (hyponym).
WordNetWordNet is a lexical database of semantic relations between words that links words into semantic relations including synonyms, hyponyms, and meronyms. The synonyms are grouped into synsets with short definitions and usage examples. It can thus be seen as a combination and extension of a dictionary and thesaurus. While it is accessible to human users via a web browser, its primary use is in automatic text analysis and artificial intelligence applications.
Ontology (information science)In 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 of discourse. More simply, an ontology is a way of showing the properties of a subject area and how they are related, by defining a set of concepts and categories that represent the subject. Every academic discipline or field creates ontologies to limit complexity and organize data into information and knowledge.
Semantic networkA semantic network, or frame network is a knowledge base that represents semantic relations between concepts in a network. This is often used as a form of knowledge representation. It is a directed or undirected graph consisting of vertices, which represent concepts, and edges, which represent semantic relations between concepts, mapping or connecting semantic fields. A semantic network may be instantiated as, for example, a graph database or a concept map. Typical standardized semantic networks are expressed as semantic triples.
