The selection of the topics/categories has not been made at random, but responds to the guidelines included in the so-called Technical Interoperability Standard for the Reuse of Information Resources (NTI-RISP) approved by Resolution of February 19, 2013, of the Secretary of State for Public Administrations.
The selection of a topic/category provides the user with the possibility of knowing the data available in the portal related to a specific subject.
The complete list of categories established by the Technical Standard can be found at the following link Taxonomy of primary sectors of https://datos.gob.es/es.
As an example, information on agriculture would be included in the Rural Environment category, information related to bus lines and schedules in Transport and historical heritage in Tourism, Culture and leisure or Urbanism and infrastructures.