Any Two Pages on the Web Are Connected By 19 Clicks or Less

According to Hungarian physicist Albert-László Barabási, any two pages on the internet can be connected by at the most 19 clicks.  That’s the maximum ‘Kevin Bacon factor’ if you will…

Barabási’s findings, published yesterday in Philosophical Transactions of the Royal Society, involved a simulated model of the web that he created to better understand its structure. He discovered that of the roughly 1 trillion web documents in existence—the aforementioned 14 billion-plus pages, along with every image, video or other file hosted on every single one of them—the vast majority are poorly connected, linked to perhaps just a few other pages or documents.

Distributed across the entire web, though, are a minority of pages—search engines, indexes and aggregators—that are very highly connected and can be used to move from area of the web to another. These nodes serve as the “Kevin Bacons” of the web, allowing users to navigate from most areas to most others in less than 19 clicks.

Barabási credits this “small world” of the web to human nature—the fact that we tend to group into communities, whether in real life or the virtual world. The pages of the web aren’t linked randomly, he says: They’re organized in an interconnected hierarchy of organizational themes, including region, country and subject area.

Interestingly, this means that no matter how large the web grows, the same interconnectedness will rule. Barabási analyzed the network looking at a variety of levels—examining anywhere from a tiny slice to the full 1 trillion documents—and found that regardless of scale, the same 19-click-or-less rule applied. [smithsonian]

This revelation does however highlight the ‘connectedness’ of the internet relies heavily on a few crucial points (search engines).  What would happen if Google or Bing failed and couldn’t be restarted?  You and I would suffer, and so would the internet.