No one knows for sure how many individual pages are on the web, but right now, it’s estimated that there are more than 14 billion. Recently, though, Hungarian physicist Albert-László Barabási discovered something surprising about this massive number: Like actors in Hollywood connected by Kevin Bacon, from every single one of these pages you can navigate to any other in 19 clicks or less.
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.