How do you imagine the Web (or do you at all)?
I imagine it like this:
First, let’s imagine a small website. The website typically has a hierarchical structure, i.e. a tree:
Here, the circles are web pages – the big one is a homepage, smaller circles are the next level of hierarchy and so on. The web pages of the same level are drawn at the same distance from their parent web page.
The web pages are connected with tree links. “Tree” links are links that can connect just a parent with a child in a hierarchy, hence the name.
As we know, trees can be organized in a number of different ways. Also, websites can vary from a few web pages to millions of them, causing a huge variety of possible arrangements and shapes.
But the Web with just tree links would be a boring place. Websites would be isolated islands not aware of each other. Also, the navigation between the web pages on a single website would be limited by the hierarchical order of web pages. The only way to get to a desired destination would be to find the right branch, and then, one node at a time, travel to your target web page. Just like you do everyday browsing through the folders in your file system.
Fortunately, there is another kind of link: a hyperlink. This link is not restricted by a hierarchical order and can magically connect any two web pages, not just in a single website, but on the whole Web. No matter how low in a hierarchy, when it comes to a hyperlink, every web page is equal.
Therefore, hyperlinks “break” the hierarchical order of a website and cause the tree to become a graph, so we can also call them “graph” links. An analog in a file system is a shortcut that allows you “teleporting” to any place on the disk.
With added hyperlinks, our four websites will look something like this:
We have added the third dimension. That way we ensure that the hyperlinks don’t overlap.
Now, let’s try to imagine that our little “Web” is growing. New domains are registered and new websites are emerging. New hyperlinks are added pointing from the new web pages to the existing ones and vice versa. As we see in the next image, everything is pretty much the same, just on a larger scale.
With a fair amount of certainty we can conclude that if we add more and more web pages and finally reach the real size of the Web, the same basic structure will remain.
However, there is a problem. In this kind of a structure, not all websites are equal. The distance of an average website is much shorter if you’re near the center, meaning the centrally positioned websites are more privileged than the ones placed on the edge. This arrangement doesn’t reflect the democracy of the Web. Also, this kind of spatial structure is not elegant in a sense that results in very long hyperlinks connecting distant parts.
Maybe we could give up a “flat” arrangement of the websites and allow them to float in 3D space, perhaps something like stars in the Universe. However, this doesn’t solve the problem. Still there are central parts and periphery parts like in the previous model.
We need a structure in which there won’t be any “edges”. An elegant solution would assume a 3D geometrical object that enables desired equality. We can imagine that the flat surface in the previous image is actually the surface of a big sphere that just looks flat when looked from a close distance, just like the Earth. A sphere ensures that all web pages are equal and controls the maximum length of a hyperlink. The most distant web page is no more distant than a diameter of a sphere.
The interiour of the sphere is white because of the vast amount of (white) hyperlinks. If we grab a website and pull it from the sphere, this white matter of hyperlinks become clearly visible.
Although this model looks pretty elegant, it still has a problem. The Web is growing constantly, meaning that the sphere is getting bigger and bigger. In a purely theoretical model, this doesn’t make much difference. But imagine the Web realized in the physical world. It would eventually become so big that the cost of material for hyperlinks would be extremely high.
In addition, the maximum size of the Web would have to be in some way restricted, not just due to cost but for practical reasons. Perhaps it would be placed in some kind of container, which would be holding it and possibly protect it from the environment. So how the Web would grow in such limiting conditions?
Well, the “cortex” of the Web can be folded, allowing much larger surface for websites to grow, while retaining the basic idea of equality and keeping the hyperlinks relatively short. Unfourtunately, I’ve not provided an image for this. But I have no doubt that your brain is capable of creating one.
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