“Things have always been changing on the Internet, sometimes gradually and sometimes very rapidly, but always evolving without a precise general design.” Indeed. My first encounter with the Internet, around 1991, was with the now long-forgotten Gopher, the precursor of the fledging Web. I was overwhelmed by the sheer amount of information I stumbled upon, which in retrospect pales in comparison with any of the bigger portals in existence today. Its popularity and size have been on a constant uphill climb ever since, which explains why two statistical physicists, Romualdo Pastor-Satorras and Alessandro Vespignani, had taken on the task of describing the major influencing trends that shape its development and its present form.