There are various interpretations of the semantic desktop.

The vision of the semantic desktop can be considered as a response to the perceived problems of existing user interfaces.

You can see an overview of some of the new semantic desktop features in the Mandriva Labs blog.

In practice most projects related to the semantic desktop make use of Semantic Web protocols for storing their data.

There are substantial efforts towards the implementation of a semantic desktop in FOSS communities.

Strigi and NEPOMUK are working together to help create a semantic desktop search.

KDE Plasma Workspaces require Strigi as core component of the new semantic desktop technologies.

Mandriva's developers tout tight integration with KDE's semantic desktop framework, called Nepomuk, as one of the major features of the new version.

The most notable of those applications is the Haystack client, a research personal information manager (PIM) and one of the first to be based on semantic desktop technologies.

The semantic desktop is an attempt to solve some or all of these problem by extending the operating system's capabilities to be able to handle all data using Semantic Web technologies.

Some operating systems such as BeOS have database filesystems which store metadata about a document natively in the filesystem, which is a move towards a more semantic desktop.

The Java-based implementation of NEPOMUK was finished at the end of 2008 and served as a proof-of-concept environment for several novel semantic desktop techniques.

GNOME Activity Journal is a semantic desktop browser-like application for the GNOME desktop environment.

Soprano was created as a sub project under the NEPOMUK project and forms a part of the semantic desktop in KDE Software Compilation 4.

NEPOMUK, an open-source software specification for a Social Semantic desktop uses RDF as a storage format for collected metadata.

In concert with other software like Soprano, an RDF storage framework, and the NEPOMUK specification, Strigi will provide the beginnings of a semantic desktop in KDE 4.

NEPOMUK (Networked Environment for Personal, Ontology-based Management of Unified Knowledge) is an open-source software specification that is concerned with the development of a social semantic desktop that enriches and interconnects data from different desktop applications using semantic metadata stored as RDF.