In Chapter Five, what is the most important difference Carr identifies between the Net and most of the mass media it replaces, like television?

In Chapter Five, Carr says that the bidirectionality of the Net is the most important difference between it and most of the mass media it replaces, like television. In other words, users can both access information and content on the Net, but the same users can also easily create, upload, and distribute content on the Net as well