Anyone who has experienced the Web is familiar with the behavior of the links.
If we imagine the Web as a vast ocean full of islands that represent webpages, the behavior of the links would be very similar to the operation of a catapult. We move around this imaginary world of islands of information, jumping from one to another, using catapults as one-way tickets to the next destination.
The browser gives us the option to point a catapult back to the island we visited previously , and we can pact with other islands to set catapults pointing each other to create a network that allows us to travel in both directions. But this scenario is not the norm, because the easiest-to-implement catapult design for the link  does not include two-way communication by default, meaning that if we want something that resembles the behavior of a bridge but using catapults, we need to put some extra energy to make it happen.
A real-world example to illustrate how this additional effort is required in the current paradigm of the Web can be found on the concept of a backlink, “a link on someone else’s website that sends the reader to your site” , and the billion-dollar industry created along with it .
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