"In CHPortal, ontologies are organized in groups and tagged with categories. Typically, groups associate ontologies from the same project or organization for better identification of the provenance. Whereas categories are about subjects/topics and enable to classify ontologies. The CHPortal's categories are chosen according to the UNESCO Thesaurus (https://vocabularies.unesco.org). Groups and categories, along with other metadata, can be used on the “Browse” page of CHPortal to filter out the list of ontologies."