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What is an ontology?

An ontology is a classification of concepts or topics in a given domain.

Here is an example:

  • Heroes:
    • Mythological heroes:
      • Hercules
      • Theseus
      • Sisyphus
    • Superheroes
      • Batman
      • Catwoman
      • Flash

Why ontologies are useful for a search engine?

By default, Nuclia identifies any named entities in the content it indexes.

So you can search for "Hercules" or "Batman" and get a list of results.

It will also identify relationships between entities, like when searching for "Batman", it will probably suggest "Catwoman" as a related entity, and not "Theseus".

By providing the Heroes ontology, you can now search for contents mentioning mythological heroes and get the expected results.

You are not meant to define everything in your ontologies, Nuclia is able to extract the meaning of the contents it indexes, so common concepts will be properly managed and corresponding search results will be consistent.

You will need to define ontology for concepts that are specific to your domain.