My friend Salim Ismail has written a good post about the evolution of the Internet (in fact, the piece has the imaginative title “Evolution of the Internet”) over at his excellently named blog, You’ve Got Ismail! In it he talks about the three kinds of uses to which the Internet has been put.
The first was messaging, which just involves transmitting a packet of data from one place to another. This was the underpinning of the first big-time Internet application: e-mail, which got rolling in the 1980′s. The second was request-response, which is what HTTP is all about, and which made possible the explosive growth of the World Wide Web in the 1990′s. The third, which is just getting underway, is publish-subscribe, in which content on the Internet, which up until now has had to be actively fetched by the user, is able to announce itself to all interested parties.
Salim gives a clear and cogent account of it all. He has also added a post today, I see, in which he explains the important distinction between prospective and retrospective search.
Do take a look; what he is describing is the Next Big Thing.