Metadata are entries that describe a resource in our repository.

Basically metadata describes documents, objects or services and contains information about their content, structure or form. More abstractly metadata is a description of data or "data about data". Bibliographic data sets and catalog entries in library catalogs can be seen as a kind of metadata.

This repository is using metadata in the Dublin Core Metedata Element Set (short Dublin Core (DC)) which has fifteen basic elements. Dublin Core is the result of international efforts to reach a collective consensus in describing electronic objects (in the broadest sense). The Library of Congress (LoC), the Online Cataloging Library Center (OCLC) and several national libraries are dealing with Dublin Core in many projects and are close to introduce the system respectively.

External systems are able to refer to them in their search results. This makes it possible to find the publications contained in OPUShtw using other catalogues, including that of the German National Library, WorldCat, or in scientific search engines such as Google Scholar or Base.

The metadata is input by the authors themselves when they upload their work. The library reserves the possibility of making corrections to them.