
There are an estimated 14 billion+ web pages in existence. But even with this massive number, you can navigate from any single one of those pages to any other in 19 clicks or less.
That’s the finding of Albert-László Barabási, a Hungarian-Romanian physicist and network theorist. He’s constructed a simulated model of the web, and in doing so discovered that of the ~1 trillion web documents in existence (this figure includes every image or other file hosted on every one of the ~14 billion web pages), most are poorly connected.
In other words, they’re linked to just a few other pages or documents.
But the web also has a smallish number of pages associated with search engines, indexes and aggregators that are highly connected and can move from one area of cyberspace to another.
It is these “super-potent” nodes that allow people to navigate from most areas to most others relatively easily.

Hence Barabási’s “19 clicks or fewer” finding.
He posits that the web mirrors fundamental human experience: the impulse for people to tend to cluster into communities (both real and virtual).
Thus, the pages that make up the web aren’t linked randomly. They’re part of an interconnected organizational structure that includes country, region, subject/topic area and so forth.
That interconnectivity is illustrated nicely in the Opte Project’s “map” of cyberspace. This endeavor, spearheaded by Internet entrepreneur Barrett Lyon, gives us intriguing visualizations of the web and how it is interconnected.
The resulting picture (see above) is impressive, visually arresting … and even a bit scary.