What can be the future of the web ? This question leads us to wonder how this new field will change the knowledge system in the world and what role is foreseen for NLP in the web 3, 4 and 5, i.e. the Internet to come. It is true that the web for many people means doubts. The treatment of information is very superficial. It is important for everybody to know who is who and who said what, who really does what. We must bring common sense and reason on the Net... We must take into account the specificity of each domain. All fields are concerned, but some very deeply : medicine, sciences such as chemistry, commerce, oil and energy, for instance... Exchanges between researchers have become the rule, the results of research laboratories are available to all and exploited in collaboration.