What is Wikidata

In recent decades, different initiatives have emerged in public and private institutions with the aim of offering free access to the data generated in their activity to anyone. In particular, there are two types of initiatives: open data portals and linked data portals. Open data portals are characterized in that it offers access to its content in the form of a REST-type web services API that acts as a query language. On the other hand, linked data portals are characterized in that its data is represented using ontologies encoded by RDF triplets of the subject-predicate-object style forming a knowledge graph. This chapter presents a set of value-added service creation cases using the information stored in open data and linked data repositories. The objective is to show the possibilities offered by the exploitation of these repositories in various fields such as education, tourism, or services such as the search for taxis at an airport.