Nepomuk
Nepomuk is the swiss army knife of the semantic desktop. It defines data structures for almost any kind of data you might want to store in a workstation machine.
Subpages:
Nepomuk Information Element (NIE) – Top classes in the ontology. Almost everything else is subclass of these.
Nepomuk Annotation Ontology (NAO) – Tags, ratings and other common annotations to all classes
Nepomuk File Ontology (NFO) – About files and other desktop resources.
Nepomuk Contacts Ontology (NCO) – All about contacts. Rough equivalent of the VCARD standard.
Nepomuk MultiMedia (NMM) – Description of multimedia objects like Music, Video and Images
Maemo Feeds Ontology (MFO) – Model for feeds and alike online streams
Simplified Maemo Location Ontology (SLO) – Ontology for locations and landmarks
Tracker-specific annotations Ontology – Internal tracker properties
libosinfo-specific annotations Ontology – libosinfo properties
The results of the search are