How is internet traffic generated?

Question

Computer networks

Stupid question to which I can not find a specific answer. The Internet, as I understand it, is simply the connection of many computer networks to each other. Thousands, millions, and now billions, all of them! Fiber optic cables are laid along the bottom of the ocean, combining entire continents. The owner of the cable sells his services to providers, who in turn sell their services to us. Owners spend this money on maintenance of these cables. At the end (or whatever you call it) of the fiber optic cable, there must be a machine that converts the signal into electrical and transmits it to our computer, which in turn processes it in the same way.
- this is understandable, it is logical and everything adds up to a beautiful puzzle. But one question remains. What is Internet traffic and HOW IT IS GENERATED / GENERATED / FORMATED / APPEARS. Internet traffic is simply information that is transmitted from user to user. I looked at dozens of articles and did not see a clear explanation of this construction. “Search engines generate traffic. Facebook generates the most traffic on the web. Blah blah blah" and nothing specific. I give a request to get a file from the computer, it gives me the file and the browser loads the web page. How could I generate traffic if I just issued a "request" command? That is, I, in fact, only took the information, there was an interaction between two users, but how was the traffic formed? Megabytes, gigabytes - I only take.
Explain how traffic is generated.
PS Additional optional question. What is the reason for the incredible data transfer rate? Indeed, in fact, they simply let light through the glass, but at the same time this light must also be processed.

Answer 1

When you, as a user, go to the toaster, you will download a page on which you can see questions. This traffic was generated by a toaster.
When you go to YouTube, YouTube sends you a video, so YouTube generated video traffic.
Many users go to Google to find something and then follow the link. But to go to Google, to get links is to download traffic generated by Google.
Users usually do not generate traffic. Well, unless you communicate via Skype with a friend, then you generate traffic for each other. But in almost all modern messengers, you exchange through its server, so even here there is traffic that "messenger generates".
Sitting on Facebook - you download all the traffic from it. Yes, of course, you generate part of the traffic when you upload a new photo to Facebook. But Facebook will generate much more traffic when 100 of your friends (or friends of their friends) download this photo from it.
ps The baud rate is related to the frequency of the signal.

Answer 2

There is a book where everything is popularly described: https://www.ozon.ru/context/detail/id/26326082/

Answer 3

To begin with, we need to understand that in this context there are two meanings of the word "traffic":

1. There is "technical traffic" consisting of data packets. When I turn on the computer and access the site (for example, here) - then my computer first sends out ARP requests. Then my computer sends a DNS request, and the DNS servers communicate with each other over it. After I set the IP address of the site - my computer sends an HTTP request there and receives the page; and to it - links to pictures on which additional inquiries are made. In short, a lot of packets are sent out - each request can consist of one or more packets, and a packet can go through many hops (connections between switches / routers).
2. And all sorts of managers and SEOs use the word "traffic" to refer to visitors who come to the site. Those. if I placed an advertisement or achieved the appearance of links to my site in the search results, then the advertising banner network or the search engine generates “visitor traffic” for me, which, with skill and luck, I can monetize.

The incredible data transfer rate is due to the fact that the real world allows you to transmit an analog signal, into which you can stuff a lot of data. Wikipedia says that visible light has a frequency of 390 THz to 770 THz - this number can be taken as the theoretical limit for the data transfer rate over an optical channel (on a single fiber), counting one hertz per one bit-per-second. This is precisely the theoretical limit - the actual speed available can be limited by many factors.
Although it is possible to shove light from several lasers operating at different frequencies into one fiber. In short, it's hard.
Processing speed - is determined by other factors, there are many of them. It's difficult here too. Moreover, to understand all this, you need to know well mathematics and physics, incl. quantum mechanics - and this is not available to everyone.