Re: Who created the Internet and how?

The Internet is a set of rules for passing information from place to place. That information could be an email, a video file, a webpage, or a financial transaction. Now consider how to get that information from one point to another. For instance, suppose that I want to drive from Claremont, CA (where I live) to New York City. I would pull out a map, plot out a route, and then drive.

That works because the map fits in a reasonable amount of space, and because new roads and cities are built very slowly. On the Internet, none of that is true! The number of cities (called nodes in a network) grows very quickly. This image shows what the Internet might look like as a direct map. Pretty, but not too useful.

So instead, the designers of the Internet, a United States military research agency called ARPA (that stands for Advance Research Projects Agency) used a clever idea invented by Paul Baran, Donald Davies, and Leonard Kleinrock called packet switching. Here's how it works: instead of keeping the entire map, each node should just locate its nearest neighbors. Then to get from point A to point B, pass the information along to a neighbor that is slightly closer to the final target. The Internet was ''created'' when the set of rules (called the Internet Protocol, or IP) for passing from one neighbor to the other was implemented to pass information between two nodes, one at UCLA in Southern California, and another at SRI in the Bay Area.

By 1971, there were 15 nodes, but exponential growth is, well, exponential. By of June 30, 2009 the population of Internet users was about 1.67 billion. A simple idea, but one of the best of the twentieth century!

Mark Huber