The definition of Open Data is compliant with the Open Definition and it can be summarized in the statement that “a piece of data is open if anyone is free to use, reuse, and redistribute it – subject only, at most, to the requirement to attribute and/or share-alike”.

Tim Berners-Lee, the inventor of the Web and Linked Data initiator, suggested a 5-star deployment scheme for Open Data. Examples for each step of the stars and costs vs. benefits that come along with it are provided in this website.

Together with Open Access, Open Data is another fundamental enabler of Open Science and the Sci-GaIA project consortium promotes Open Data at the biggest possible “number of stars”.

Indeed, the Sci-GaIA Open Access Repository and the e-Infrastructure Knowledge Base are examples of 5-star Open Data services.