Mathesis is a special department of Crete University Press aiming to create and offer free online courses that will fulfil the highest international standards of MOOCs. Mathesis online courses are hosted at the greek edition of OpenEdX platform -the same platform that Harvard and MIT use for their EdX Courses- and is provided with all the appropriate technical features for MOOCs. In Mathesis, however, we insist that "media is not the message" and we strongy believe that there is no technology or platform that could conceal a (potential) absense of educational content. So, it's a fundamental prerequisite for Mathesis' success to engage for its' courses excellent academic instructors both from Greek universities and from international academic institutions, that can meet the challenge of high level online courses.Mathesis online courses which began in Autumn 2015 with the kind support of Stavros Niarchos Foundation, are not only aimed at students, scientists and teachers, but also at every educated citizen that is interested in science and knowledge.