Frequently Asked Questions

Basic features of the Deutsche Digitale Bibliothek (DDB)

What is the DDB?

The DDB is Germany’s central, national portal for culture and science. The portal, wholly organized and funded by the public sector, has the ongoing aim of linking up the digitised inventories of Germany’s cultural and scientific institutions and making them available to the public.

The DDB is the national data aggregator for Europeana.

The DDB is a network of the cultural and scientific institutions in Germany. It enables and encourages them to network, cooperate and to develop and use together services and innovative tools. These make possible, in particular, new and more effective forms of presenting, managing and processing digitised contents.

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What is offered in the DDB?

In short: the cultural and scientific heritage of Germany in digital form.

This includes digitised collections and indexing information from cultural and scientific institutions such as libraries, archives, museums, monuments offices, media libraries, universities and other research organisations. The DDB provides central access to digital images ranging from books, documents and files, paintings, statues, installations and monuments to movies and music.

The number of objects in the DDB is continuously increasing. Below the search field on the home page the current total number of objects is displayed. It is also reported how many objects contain digitized media.

A map showing a constantly increasing number of organisations and institutions (already totalling more than 2,100 in March 2014) provides an unique overview of Germany’s cultural and scientific landscape and one that is being steadily expanded and updated.

The aim of the DDB is to offer digital objects from all sectors and in all conceivable types of media (initially text, sound, images and film). At the beginning, some individual areas like libraries will be able to present more content, because they started to digitise their collections earlier than other sectors. In the long term, a well-balanced variety of objects and the broadest possible overall range of items should be available.

The DDB does not as a rule have access to the actual digital items. Such objects located using the DDB are displayed in their complete and high-resolution version in the Web portals of the institutions involved who have provided them and these sites are accessed via a link on the DDB website.

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Who can use the DDB?

Anyone can pursue his or her private or professional areas of interest, gain more in-depth knowledge and gain new inspiration by using the portal. Tourists and people interested in culture can inform themselves conveniently about cultural activities and facilities and about a city’s or region's academic/scientific institutions. The DDB is of particular interest to academics and scientists, students, teachers and school pupils. Journalists and publishing houses can find information here for their publications. And cultural and scientific institutions can use the DDB as a platform for exchanging services, tools and data and, in this way, improve their own data and network their activities with one another.

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Search functions

How can users search for content in the DDB?

The portal offers standard search functions where users can research into the entire inventory of items by entering search terms. An advanced search function is also provided. Various filters, also called facets, will be available to narrow down the search results or act as an alternative search function. The results list changes dynamically depending on what you select in this faceted search. In future, search results will also be visualised and narrowed down using a map. Furthermore, users can navigate between the objects found using semantic references and, in so doing, open up unexpected content and contexts. Information on artists, authors etc. will be displayed on ‘People’ pages, from where users can access individual objects in the DDB that are related to the person concerned. This is where the great advantage of the DDB lies, as it brings together collections from different fields and environments, thus highlighting the connections and cross-references that are not clearly visible on the websites of individual institutions or on domain-specific sites (e.g., purely library-based portals). This is a feature unique to the DDB.

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What filters/facets are available to narrow down the search results?

Currently, the following facets (search filters) are available: time, place, person/organisation, keyword, language, media type, section, data supplier. It is possible to distinguish between the different roles a person might have in relation to a certain object (e.g “Involved in” [a work by Goethe] and “Referenced in” [a biography on Goethe]. The Time facet allows users to narrow a search down to a precisely determined period of days and also to specify whether the dating should be wholly or partly contained within the desired period. This is however only a temporary situation and further nuances are planned, e.g. for the Location facet.

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Further development

What does the roadmap for the period following the launch of the first full version look like?

Ongoing improvements to the individual DDB components, especially regarding the portal itself and the quality of data, are planned for the period after the beta phase, too. Feedback received from the users will will continue to be studied. The next enhancements are likely to involve Discovery functions, the networking of objects and further improvements to the search function.

More virtual exhibitions, put together by expert curators, will clearly show the diversity of the material made available via the DDB. What is more, the participating institutions can use the DDB platform to exchange ideas and information with one another. A ‘service portal’ is also in the pipeline.

An API (application programming interface), a preliminary version of which has been available since November 2013, is already allowing the decentralised development of services associated with the DDB, e.g. specific applications for smartphones and tablets. The API is constantly being developed and adapted; in the medium term the interface should be even better at coping with Linked Open Data (LOD) scenarios.

Even after the launch of the first full version, then, the DDB will not be in its “finished” state, because the process of digitising the extremely diverse inventory of Germany's cultural goods still has a long way to go, new works that also need to be included are constantly coming into being and the constantly updated technical developments also must be taken into consideration.

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What is planned with respect to content expansion?

At the launch of the DDB the Library was already preoccupied with how to win over cooperation partners and data providers so as to expand the data sets visible to the user. In the meantime this focus has increased. We are very confident that we will be able to gain many more cooperation partners and data providers and thus significantly increase the number of objects that can be found via the DDB. At the current time, approx. 2,100 institutions have already registered as cooperation partners and the trend is continuing. The DDB, of course, also sees the necessity of actively seeking new content and will be doing so in the future.

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Is all available content freely accessible?

A distinction must be made here between access to DDB material and the use made of this content:

  • The DDB portal does not have any access restrictions whatsoever – everything is freely available. At the present time, the DDB only provides access to objects that are also openly available at the participating cultural and scientific institutions – and therefore does not contain any access-restricted or pay-for contents. A circle of experts are currently discussing expanding the access to content provided via the DDB.
  • The utilisation rules for the digitised objects are determined by the cultural and scientific institutions themselves.

Using the DDB itself is free of charge in all cases.

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What restrictions are imposed on the DDB by copyright?

Digitising protected works and/or making them publicly available constitutes a utilisation that is subject to permission under copyright law. When using any content made available, the existing copyright and other intellectual property rights must be observed in full. This means that works protected by copyright can only be digitised and made publicly available with the consent of the owners of said rights. Where consent is virtually not possible, that is, in the case of so-called “orphaned works”, it remains to be seen whether a new legal regulation will make it possible to access the corresponding works, if possible, even without the consent of the copyright owners.

As the digital objects made available via the DDB are not located in the DDB itself, but in the respective institutions (and can be accessed there), these are then responsible for any necessary access controls and for charging costs for the use of works that are not in the public domain.

The DDB has introduced a licensing model that allows participating institutions to select from a bundle of licenses and license notices. In future all digital material viewable in the DDB will be accompanied – where possible - by a notice stating the conditions of use or be tagged with a Creative Commons license.


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Was ist das Deutsche Zeitungsportal?

Im Deutschen Zeitungsportal befinden sich digitalisierte historische Zeitungen deutscher Kultur- und Wissenseinrichtungen, die unsere Datenpartner – zumeist Bibliotheken – der Deutschen Digitalen Bibliothek zur Verfügung stellen. Weitere Informationen zum Zeitungsportal finden Sie hier.

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Questions about organisation

What led to the DDB being set up?

The decision to set up the DDB was taken by the Conference of German Minister Presidents in October 2009 and the Federal Cabinet in December 2009. The foundations for this were the shared key points of interest of the federal Government, the Länder and the municipalities as well as an administrative and funding agreement between the Federal Government and the Länder. To set up the infrastructure, the Federal Government provided upfront funding of around 8.5 million euros until the end of 2011. One aspect that influenced the emergence of the DDB was a request by the European Commission to the member states that they make efforts to digitise and provide access to cultural and scientific information as part of the European Digital Library (Europeana) project. The DDB therefore simultaneously acts as a central national partner of Europeana and in this way enables German cultural institutions to take part in this European project. A selection of background information, foundations and framework conditions concerning the realisation of the Deutschen Digitalen Bibliothek can be found here.

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Why does the DDB exist alongside Europeana?

The DDB is to a certain extent the German section of Europeana. The Europeana combines the cultural heritage of all member states of the European Union making it accessible worldwide, that is, the member states of the EU make their cultural and scientific resources available to the public at large. The EU Commission, as the body responsible for Europeana, is convinced that the knowledge society can only function in the future, if free and democratic access to knowledge is guaranteed for everybody. The Deutsche Digitale Bibliothek is involved in this process. The EU Commission, as the body responsible for Europeana, is convinced that free, democratic access to cultural heritage must be guaranteed for everyone so that the opportunities that go hand in hand with digitisation can be used for the development of our society. This is something that the Deutsche Digitale Bibliothek is collaborating in.

The DDB not only sees itself as a technical instrument providing access to cultural treasures, to some extent the information and services it provides also go beyond the content of the Europeana. The DDB will form a network for the participating cultural and scientific institutions in Germany and provide mutual support and an exchange of experience, technologies and services. In the semantic networking of items, too - e.g. the incorporation of normed data - the DDB is in some respects ahead of Europeana.

In addition, the DDB and Europeana work in close coordination with one another. There are already cooperation projects between the DDB and Europeana for technical, organisational, legal matters, etc. and these will be expanded in future by cooperation between the DDB and other national aggregators.

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Who funds the DDB and how?

The DDB is funded by the German Federal Government and the Länder on the basis of the administrative and financing agreement from December 2009. The Federal Government provided around 8.5 million euros to set up the infrastructure by the end of 2011 and, to set up and operate the DDB infrastructure, the Federal Government and the Länder have jointly pledged an additional 7.8 million euros by the end of 2012. By 2015, an additional annual sum of 2.6 million euros will have been made available for running the DDB. After that, the Federal Government and the Länder will decide on the further funding of its operation based on an evaluation of the existing structures and work achieved in the interim period. Furthermore, in 2013 the Federal Government also invested an additional 1 million euros in the expansion from beta to full version of the DDB and another 4 million in special projects for digitising cultural items in Federal Government facilities, the results of which will be entered directly into the DDB. During the beta phase the Länder, too, provided 300,000 euros to help fund work to expand the functionality of the DDB. As such, the investment volume for setting up and operating the DDB portal amounted to 24 million euros by the end of 2013.

The total funds spent by the Federal Government and the Länder for the DDB, however, are considerable higher as only a fraction of the costs for the production, collection and preparation of the approx. 20 million objects and/or digitised items visible in the DDB so far, which mainly took place as part of measures subsidised by the Deutsche Forschungsgemeinschaft - DFG (German Research Community - DFG), have been included in the investment volume for setting up and operating the DDB infrastructure.

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Where is the DDB head office?

The head office of the Deutsche Digitale Bibliothek is located in the Stiftung Preußischer Kulturbesitz (Prussian Cultural Heritage Foundation) in Berlin. The office can be contacted at geschaeftsstelle [at]

The DDB technical coordination department and the Service Center, which fields enquiries from interested cultural institutions, are located in the Deutsche Nationalbibliothek in Frankfurt. The Service Center can be reached on service [at]

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Getting involved

What advantages are there for institutions who make their contents available via the DDB?

Central access via the DDB takes users unfailingly to the digital cultural works they are searching for. Since the works are always associated with their place of origin, both the works and the institutions themselves become more visible and known, meaning that they can expect an increase in visitor numbers both online and offline. In addition, the institutions can exchange ideas and experiences with other institutions via the DDB network, and support one another. The DDB also provides tools and services that help institutions to optimise their digital content and how it is presented and prepare digital objects for publication. The DDB consistently posts legal notices relating to user rights and reflecting information provided by the relevant institution, in an effort to promote the correct usage of content.

For individual sections of cultural items like the archives, the DDB will also act in future as Germany’s central reference instrument for index information and digitized archived material.

On request, the metadata and derivatives stored in the DDB can be fed into Europeana, the European culture portal, thereby appearing within an additional context.

From April 2014 the DDB has been giving institutions an opportunity to curate their own virtual exhibitions in the DDB, thereby increasing the exposure given to their material and raising the profile of the institution.

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Under what circumstances can an institution deliver data to the DDB?

The cultural or scientific institution first registers with the DDB as a data supplier. Any data intended for the DDB must be provided in a supported metadata format. The DDB Service Center works with its domain-specific service desks to support this process  and is happy to answer queries regarding registration, metadata formats, data transmission and any aspects of the process.

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How are data entered into the DDB?

There are two options: The institution chooses between one-off or recurring (updated) data delivery. In the case of a one-off data upload, an FTP server is the most suitable archive location and will be provided by the DDB technical service provider.

If regular data matching makes sense because of frequent upgrades or updates in the portfolio, so-called Harvesting via OAI-PMH is a good solution for retrieving the most recently updated data from the providing institution. The DDB is ready to help you at any time to chose the best option and to implement the project.

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What exactly is entered in the DDB and made available there?

The DDB does not provide digital objects (full text, high resolution images and the like) itself, but stores and makes available the metadata and indexing information as well as derivatives of such digital objects. Metadata and indexing information are the data that describe the objects - mainly data for formal indexing and content indexing. Derivatives are excerpts from the objects or small formats, such as tables of contents, preview images and audio and video excerpts.

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Who can curate a virtual exhibition in the DDB?

Any institution providing the DDB with material. Also: curators interested in presenting Library material in more detail, as part of a themed exhibition. Interested parties are invited to contact the Service Center on service [at]

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Who can help participating institutions with questions and problems?

The Service Center provides competent advice on all DDB issues relating to registration, content and technology. Contact service [at] .

General queries regarding the DDB and questions revolving around providing the general public with access to DDB material will be answered by the Administration Office on geschaeftsstelle [at]

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If your institution (still) doesn’t have digital copies, can you nevertheless register your institution?

Yes. Even if your inventories are not or not yet digitised, you should register with the DDB and thus expand your network to other cultural and scientific institutions. In addition we are creating a cultural and scientific map as part of our work and it will show as many of Germany’s cultural and scientific institutions as possible. By registering, you will help us to realise this important objective. At the same time, you will be increasing the visibility of your institution on the web. Moreover, you may provide mere cataloguing data to the DDB.

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What (digital) content can a cultural or scientific institution enter in the DDB?

The DDB is basically interested in all objects that have a cultural value from the perspective of the individual cultural and academic institutions. Therefore, the delivering institution ultimately decides on which collections will be presented in the DDB. The DDB only reserves the right to decide what order the content will be displayed in, and makes sure that content is displayed in a well-balanced way, if it is possible and makes sense to do so. A key criterion for the inclusion of objects in the DDB is that they (or representations of them) are available online in digital form. Digital information referring to physical objects from the institutions can also be presented in the DDB, if this is necessary and appropriate in certain sectors.

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What quality criteria exist for (digital) content?

The quality criteria are based on the current rules of practice of the Deutsche Forschungsgemeinschaft concerning digitisation. (However, they do not define any criterion for exclusion.) In addition to this, there are minimum requirements for the derivatives and metadata in order to guarantee the proper presentation of the objects in the DDB. The digital object to which the metadata refer must be connected to them via a permanently functioning link (so-called persistent identifier), the stability of which must be guaranteed by the providing institution.

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Does the DDB store not only metadata but also the digital objects themselves?

The DDB only saves access information and metadata and, if desired, derivatives, that is, preview pictures, thumbnails or tables of content. The digitised item remains with the providing institution. It is accessed via a link that leads the user from the results display on the DDB interface to the object display in the Web portal of the respective institution.

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Technical questions

What metadata format does the DDB use?

The internal metadata format of the DDB is based on the Europeana Data Model (EDM). The DDB has developed a special EDM application profile that simplifies cross-disciplinary searches, semantic networking and structured layout of (digital) content and the metadata in the DDB. The Europeana Data Model is a simple, flexible model based on the linked-data principle, whereby data are modeled in Ressource Description Framework (RDF) syntax. The model is made up of 15 classes and has a special feature allowing a cultural object to be described from three different angles: as an object, as its digital representations and as its associated metadata. It enables users to establish a permanent link between objects and their contexts, for example people, places and events. On this basis it will in future be possible to provide other explorative forms of research and data presentation that go beyond individual data inventories.

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What interfaces are provided by the DDB to import data?

On the one hand, you can upload the data by File Transfer Protocol (FTP). This method is suitable above all when transferring large data volumes at once. On the other hand, cultural and scientific institutions can provide their data via a harvesting interface (Open Archives Initiative Protocol for Metadata Harvesting, OAI-PMH), which can be called up via the DDB. This method is recommended if a data set is to be updated or expanded regularly.

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What interfaces are provided by the DDB to export data?

The DDB has an interface for the transfer of data to Europeana.

Via its API, released in version 1.0 in November 2013, the DDB allows external services and applications running searches to access DDB material.

Suitable interfaces will be provided for the export of larger quantities of data. Cultural and scientific institutions can use these interfaces to retrieve their own enriched data from the DDB. This requires import interfaces and procedures on the part of the cultural and scientific institutions. The DDB is happy to advise and support its partner institutions in this process.

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How can an API benefit users?

The API is an application programming interface that allows users to access data via methods provided by the Deutsche Digitale Bibliothek (DDB). It allows the development of a range of applications that use material in the DDB, displaying it as they see fit and embedding it in a variety of contexts. The API is available to all users who have registered with the DDB portal, as soon as they have set up an access code (‘API key’) in their “My DDB” area of the portal.

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How do I use the DDB's API?

Users must verify their identity using an API key in order to use the Deutsche Digitale Bibliothek API. The key is a unique series of characters that has to be transmitted each time the user sends an enquiry to the API. All registered users of the Deutsche Digitale Bibliothek can obtain their personal authentication key for using the API. Keys can be issued once users are logged into their DDB account (“My DDB”).

Further information and a detailed description of the API can be found on

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What metadata format must be provided by the delivering institutions?

Admissible delivery formats are  DC, DenkXWeb, indexMeta, ESE, EAD(DDB), METS/MODS, MARCXML and LIDO. These formats are widely used in the respective fields. Data should be delivered in XML format, as they will be converted using XSLT-based transformers to the internal format of the DDB. If the formats mentioned above cannot be supplied, the DDB Service Center and its domain-specific service desks are happy to advise on how to convert the existing format into one of the approved delivery formats.

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