When constructing our project, we decided to create our own ontology, Plucky, to successfully and efficiently describe the variety of items and concepts our project involves. In general, for ontologies to be considered as such, they need to be defined in the OWL language. Here you can find the initial structure that our OWL file would have if we decided to fully create and implement Plucky as a serious ontology.
<?xml version="1.0" encoding="UTF-8"?>
<rdf:RDF
xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
xmlns:owl="http://www.w3.org/2002/07/owl#"
xmlns:dc="http://purl.org/dc/elements/1.1/"
xmlns:plucky="http://www.semanticweb.org/plucky">
<!-- OWL Header -->
<owl:Ontology rdf:about="http://www.semanticweb.org/plucky">
<dc:title>The Plucky Ontology</dc:title>
<dc:description>
An example ontology written for the purpose of describing ideas and events related to historical circumnavigation.
</dc:description>
</owl:Ontology>
<!-- OWL Class Definition - Entity -->
<owl:Class rdf:about="http://www.semanticweb.org/plucky#is_entity_type">
<rdfs:label>The type of object or entity being described</rdfs:label>
<rdfs:comment>The class of all entity types.</rdfs:comment>
</owl:Class>
<!-- OWL Subclass Definition - Person -->
<owl:Class rdf:about="http://www.semanticweb.org/plucky#person">
<!-- Person is a subclassification of is_entity_type -->
<rdfs:subClassOf rdf:resource="http://www.semanticweb.org/plucky#is_entity_type"/>
<rdfs:label>Persons</rdfs:label>
<rdfs:comment>Entities that are persons, also known as human beings.</rdfs:comment>
</owl:Class>
<!-- OWL Subclass Definition - Places -->
<owl:Class rdf:about="http://www.semanticweb.org/plucky#place">
<!-- Place is a subclassification of is_entity_type -->
<rdfs:subClassOf rdf:resource="http://www.semanticweb.org/plucky#is_entity_type"/>
<rdfs:label>Places</rdfs:label>
<rdfs:comment>
A particular position, point, or area in space; a location. Usually refers to towns, cities, countries or continents.
</rdfs:comment>
</owl:Class>
<!-- Individual (Instance) Example RDF Statement -->
<rdf:Description rdf:about="http://www.semanticweb.org/plucky/NellieBly">
<!-- Nellie Bly is a type (instance) of the Persons classification -->
<rdf:type rdf:resource="http://www.semanticweb.org/plucky#person"/>
</rdf:Description>
</rdf:RDF>