The multitude of data platforms and the lack of common semantics resulted in a fragmented landscape of Open Data portals. To improve the metadata exchange and to reduce duplications and inconsistencies a number of standardisation and metadata harmonisation efforts have been undertaken. Using DCAT Application profile (DCAT-AP), portals with different descriptions of metadata can adhere to a common metadata language increasing the discovery of datasets.
DCAT-AP is a specification based on W3C's Data Catalogue vocabulary (DCAT) for describing metadata of public sector datasets in Europe. The DCAT Application Profile already has been implemented by several data portals across Europe like the EU Open Data Portal and the national data portals of Belgium, the Czech Republic, Germany, Latvia, Spain and Switzerland. Many implementers use DCAT-AP natively by building local extensions on top of DCAT-AP. Learn more about DCAT-AP with the European Data Portal DCAT-AP factsheet.