Whenever we search for something on the internet, something along the lines of lemmatizing words, for example, you’d probably get better search results if you include also different inflectional forms (lemmatize, lemmatizers, lemmatized, word, etc.). Well, that’s where lemmatization comes in.
An ontology is a data structure that groups entities in domains or types (for example the entities ‘dog’ and ‘cat’ are grouped under the type ‘animals’), and establishes relations between those entities. Its uses in Computational Linguistics are vast, one of the most interesting for us is the application of ontologies for chatbot training. When two humans communicate, they have a shared knowledge of the world that they presume in any spoken interaction. However, a chatbot lacks this indispensable knowledge. An ontology can help the chatbot discern that a person can walk a dog, but a dog walking a person is not something possible in our world.