In order to make learning materials easily findable, a clear and unambiguous description of the learning materials is crucial. A description must be added to the content of each digital information source. What kind of information is it? What type of file? Who is the author? Who is the information intended for? This metadata must contain all the information the teacher needs to be able to find and use the right learning arrangement. The agreement 'Requesting metadata' mainly concerns the structure of the dialogue between the search module and the repository that offers the metadata (a repository is a facility for storing and managing digital information in a form that is accessible via the internet).