Enciclopedia Britannica has chosen to stop the printed version, and it will be only in the digital form. Also in Italy “Corriere della Sera”, one of the most important newspaper, maybe will be published only in digital from 2014. That demonstrate how we are changing the way we learn, printed-knowledge is ended, wikipedia is the new master of knowledge. Expensive and heavy books will expire but free and social content will grow up. Is now necessary a way for a correct filtration of the big amount of data.