Proceedings of the 22nd international conference on World Wide Web companion

It is our great pleasure to welcome you to the 22nd International World Wide Web Conference -- WWW 2013. The WWW Conference series has been held almost since the creation of the WWW itself, having become the premier forum where key researchers, innovators, decision-makers, technologists, businesses, and standards bodies meet to present their latest works and ideas, and discuss their vision for how the WWW will evolve -- often as a direct result of their own actions and initiatives. The conference series is organized by the International World Wide Web Conferences Steering Committee (IW3C2) in collaboration with Local Organizing Committees and Technical Program Committees. This year the conference is being held in Rio de Janeiro, Brazil, for the first time ever in a Latin American country. We are extremely pleased to offer a top quality program, as can be verified by simply perusing these proceedings and its companion volume. The Research and Practice and Experience tracks present 137 papers in 35 track sessions; the Developers track, 10 papers in 4 sessions; the Demos track, 24 demos in 3 sessions; 100 posters in an ongoing poster exhibition; 12 Doctoral Consortium papers; a W3C track reporting on the latest standardization activities in themes such as Web Performance, eGov and Open Data; and an Industry Track with presentations from major players in the WWW on Big Data and on Patents and Innovation. Complementing this, more recent preliminary results are presented in over 150 papers in 21 Workshops, spanning a myriad of exciting new and existing topics. For those seeking to complement their understanding of the major knowledge areas and research topics associated with the WWW, 22 tutorials are being offered. This program is complemented with several parallel events, such as hackathons, panels, and specialized meetings covering a multitude of new subjects.