Be honest — did you read UnHerd's "cookie policy" just now, before you clicked "accept and close"? Have you ever read one of those notices? Or do you, like me, agree to anything and everything so long as you can get to the good stuff more quickly?

The reason these annoying little pop-ups exist at all is thanks to a recent-ish law which helps you understand what's being collected about you online. It's something that probably deserves a moment of your attention. But we're spending more and more time online; who wants to waste it checking 20 tedious Ts&Cs a day?

The future of the internet will come down to tiny things like this: subtle decisions made at the engineering or regulatory level — stuff which most of us ignore because we can't be bothered to find out what it's all about. Are you curious about "digital object architecture"? Do you want to know who's behind the "Internet Corporation for Assigned Names and Numbers"? A colleague of mine once spent weeks tracking this stuff — only to conclude that internet protocols are "simply too impenetrable and boring to feel angry about". Nobody cares. Nobody, except the autocrats of the world, who are quietly trying to wrestle control over various working groups and technical decisions — to make sure they can tame the digital beast.

Given our abject dependency on it, it's scary to think of the internet as a flimsy experiment. But it's already changed shape several times over its short life: from a government-funded research project for military scientists, to an academic network, to a vehicle for e-commerce and now a platform for social content. Through it all one thing remained constant, in theory if not always in practice: the idea that the internet was a single open network which anyone could join, and where everything was connected via a standard set of protocols and rules.

According to a new book, that's about to change. Four Internets argues that the era of a single internet might be drawing to a close, replaced by a balkanised network of different versions living alongside each other. Scholars Wendy Hall and Kieron O'Hara reckon four internets in particular are already taking shape.

The "Silicon Valley" model is open and libertarian — anyone can join the network, no single authority is in charge and there are few rules about what sort of information can be transported across the network. Its modus operandi is to ask for forgiveness rather than permission. This is the original vision and remains just about still on top.