Have you ever been googleing something, and you see exactly what you need in the preview, but when you click the link it doesnt show you what you want to see?
This is because the owners of the site are trying to trick you into buying something, or registering. It’s a common tactic on the internet. When Google visits the site, it gives something called a “Header”. This header tells the site who the visitor is. Google’s header is “Googlebot”. The programmers of the site check to see if the header says “Googlebot”, and if it does, it opens up all of its content for only googles eyes.
Now, all we have to do is trick the site’s headers, into thinking that we ARE google. That’s what the site does.