Okay, okay, I know. You’re on the internet right now reading this. But the internet is kind of like electricity. Lots of people use it. Few understand what it actually is.
After this article, you will be part of the few.
A Simple Definition
So what is the internet, really? Remember that talk we had about the Cloud? About how it’s just a bunch of computers in a warehouse run by Amazon?
The internet is a lot like that. Except instead of computers, it’s networks. Routers, basically. That box with the blinking lights and the cables hiding in your attic, or nailed to the wall above the reception at the hotel, or in my case sitting on the floor in the kitchen between the pantry and the trash.
That’s what the internet is: it’s a bunch of routers used to transmit information between computers.
“On” the Internet
When you think of it like that, it’s actually a little bit funny that we say we’re “on” the internet. Nothing is “on” the internet. We are “on” nothing. We are using a computer which is connected to a giant network via a router, and we use that network to fetch information from other computers. The internet is just the sharing system.
Of course, when we think of the internet, we don’t think of the routers. In fact, the only time we ever think of routers is when we lose our connection to the internet, and we groan and go turn it off and on again. It’s by far one of the most irritating machines out there.
A Defense of Routers
But now think of all the routers in the world. All talking to each other, updating each other about their location and status and connected devices. Making notes of what other routers tell them, about where they are, and about where everyone else is. Drawing maps, so that the day you want to text your sister a happy birthday message from the other side of the planet, your router knows exactly which other router to pass the message on to. And then that router will know who to pass it on to next. Maybe that third router suddenly goes down, but not to worry. The second router will find a new one to replace it. Your message might take a few milliseconds longer, but nothing most humans would even notice. On and on, router to router.
Until it reaches a coast. A lot of people think their internet goes through satellites. It does. Sometimes. But most of the time, it actually goes under the ocean. Think about it. Giant ships slowly crossing the water, sinking a cable the size of a garden hose into the depths of the ocean. Near the coasts, they usually bury the cables to prevent interference, but out at sea? Those cables just sit on the ocean floor. That’s part of our internet too. (And if you’re wondering, yes, sea animals like anemones love making their home on said cables.)
And so for a couple of milliseconds, your message will be underwater. And then it comes up on the other side, and it’s back to the routers, all the way to the data center where your sister’s messaging app stores its information. If you’re wondering what the connection between the internet and the Cloud is, this is it right here. If the internet is the road, then the Cloud is the parking lot. And once the data is parked, yet another message will go out, router to router, until it finds the router your sister is currently getting her internet from at the grocery store. That router has the honor of delivering your birthday message to your sister’s phone.
It’s really incredible, when you think about it. About what these routers are capable of, and how quickly they are capable of doing it. So maybe don’t kick it next time you walk by.
Origin Stories
For most of us, the internet is something that only happened in the last thirty years or so. Or, if you’re Gen Z, something that’s always just been there. Hi, kids!
It’s actually a bit older than that. Like AI, the internet has its origins in the sixties. It’s a Baby Boomer.
Well, technically, it has its origins in the 1800s. Before then, if you wanted to communicate with people over a long distance, you had to send a horse, make smoke signals, or light the beacons of Gondor.
Of course, if you were French in the 1800s, and your boss Napoleon wanted to send messages to his armies really quickly, maybe you built towers, and had people on them signaling to each other with sticks and you called that the semaphore telegraph. And if you were British, maybe you took those towers, stretched wires between them, and used the batteries recently invented by some Italian guy called Alessandro Volta to send electrical signals from one tower to the next, and called that the electric telegraph. And then, if you were an American guy called Samuel Morse, you took that, and created a code of dots and dashes for it, and suddenly messages could be transmitted really fast, in hours instead of days.
The point it, lots of smart people from all over the place contributed to create a super cool transmission system that used electricity to send information broken into little bits (ha) over cables really fast. And all before 1850.
That was mostly good enough for a hundred years. Gradually the telephone came in once people realized that voices are just audio information that can also be encoded and sent over wires. But it wasn’t until the 1960s that the need for a new kind of network arose.
See, around that time, university researchers had started getting their hands on computers. Back then computers were giant machines stored in university buildings which you couldn’t just shove in your backpack. So they needed a better way to share the information on their computers with researchers at other universities.
At the same time, the US military was getting a little bit nervous when they thought about what would happen if the Soviets were to attack their telephone lines. What they needed was a type of communication that would still work even if a significant portion of it was, well, nuked.
And as a collaboration of these two groups was born – you guessed it – the ARPANet.
ARPANet
Seriously though. ARPANet is short for Advanced Research Project Agency Network. It’s quite possibly one of the only case in the world where the full name tells you less than the acronym.
No, ARPANet wasn’t the internet yet, but it had a lot of the hallmarks of it already. It connected computers. It was very fast (for the time). It even had email. And most interestingly for the military, it used a technique called packet switching, which made it very, very hard to nuke.
Packet Switching
Packet switching is arguably what sets ARPANet, and its child, the internet, apart from all others forms of long-distance communication. If a wire on a telegraph got cut, that was it for any messages being sent. If your phone line got knocked down by a tree at some point, same. Your call would immediately be cut off mid-word. But the internet? The internet always finds a way.
That way for packet switching is to break a message into little pieces, called packets. Each piece is wrapped in an envelope of sorts, and gets an address slapped on it. These packets of data get fed into the network, and each one independently finds its way to its destination. Each time a router receives a packet, it reads the address on it, checks its map, and chooses where to send the packet. Not all packets going to the same place necessarily get sent along the same route. The router’s map might get updated mid-message. Some connection might fail, or a better one might come online. The destination computer simply collects the packets as they arrive, and once it has enough of the pieces, it can rebuild the message.
And this is a really powerful concept. Imagine you’re writing a paper letter to a friend. But instead of just putting it into an envelope and mailing it, you cut it up into pieces, and send each piece in a separate envelope on a different day. Even if one of the envelopes gets lost along the way, or the Soviet Union nukes your local post office, it’s still likely your recipient will get at least some of the pieces, hopefully enough to understand your letter.
ARPANet to Internet
Now ARPANet was pretty cool, but it suffered from one major problem. The problem was other people. Specifically, other people setting up networks for computers to communicate over, which worked differently than ARPANet, meaning ARPANet couldn’t talk to those computers. Imagine if IPhones were unable to call landlines, or Android phones. That’s what it was like.
Now the reason IPhones and Android phones and all other phones can call each other is because of protocols. A protocol is a set of rules that everyone agrees to use, because otherwise misunderstandings happen and stuff doesn’t work.
In the case of phones, protocols are set by, among others, the International Telecommunications (formerly Telegraphy) Union. These are the people who made everyone agree that country codes should be at the start of phone numbers. Imagine if one phone provider suddenly decided they were going to put the country code at the end. They wouldn’t be able to call anyone out-of-network. Nobody would be able to call them. They would be separate, stuck in their own network. Or worse, what if China suddenly decided they were going to use the USA’s coveted +1 country code? You’d call someone in the US, and depending on your cell service, your call would get routed to China.
That’s exactly what was happening with networks. New networks were popping up all over the place, like CYCLADES in France, and BITNET for IBM computers. And they were doing everything differently. They put together their packets differently, and identified their computers differently, all with the consequence that they were incompatible with other networks. The whole point had been for computers to talk to each other, and now everyone had the technology, but they still couldn’t do it.
What ARPANet, and all the other networks needed, was a new protocol. One protocol to rule them all.
They got two instead.
TCP/IP
TCP/IP stands for Transmission-control Protocol/Internet Protocol.
The Transmission-control protocol sets the rules for how packets should be put together. The goal of TCP is that any router from any network can find the packet’s address, and any computer can open the packet and read it. It’s the internet equivalent of putting your letter in an envelope with the delivery address in the center of the envelope, and the return address in the top left corner. Without these rules, you’d keep getting your own letters delivered back to you. Or potentially tossed in the trash because the postal service couldn’t figure them out.
The internet protocol sets the rules for how addresses are given to computers so that even computers in other networks can find them. IP addresses are basically the phone numbers of the internet. You want people to be able to call you? You need a proper number with the country code at the front, just like everyone else.
These two protocols were created by ARPANet’s daddies, Bob Kahn and Vint Cerf, and introduced to ARPANet in 1974. Once other networks adopted these protocols, suddenly they were able to exchange packets with ARPANet. The networks could network. A giant super-network was born, connecting all the computers on all the networks with Internet Protocol addresses.
They called it the internet. Short for Inter-Network.
A More Complete Definition
I don’t usually do this, but I may need to go back on my earlier simple definition.
Not because the earlier one was wrong. The internet is just a set a of routers. But now that we’ve gone over the concepts, we can actually be more accurate.
The internet is a set of routers belonging to many different networks, which can communicate with each other because they use the same message format, and have a shared addressing system to find computers.
Beautiful.
Online
So when you use the internet, what actually happens?
Take this blog. I write it on my computer. My computer is connected to the internet via my router, and has received an IP address. When I publish this article, I assign it a URL (uniform resource locator, another winning acronym). I upload the blog to the internet under this URL. In this case the URL is https://whatistechword.com/what-is-the-internet.
Now when I say “upload”, what I mean is that I use the internet to send the article and the matching URL to the Cloud server of the company that stores this site for me. This Cloud server will be responsible for sending the article to whoever accesses the matching URL, whatever the time and place they are in the world.
In order to be able to do that, the Cloud server sends the URL to be saved on a DNS, short for Domain Name Server. The DNS is like a giant phonebook for the internet.
So when you excitedly open your internet browser and type in the URL to read my new post, your computer actually starts by asking the DNS for information about the URL. The DNS will look up the URL and find the entry sent by the Cloud server. It will then give your computer the IP address of the Cloud server. Once your computer has that, it can send a request packet through the routers to the Cloud server at that IP address. The Cloud server reads the request packet, pulls out the article, breaks it into packets, and sends them to the return address, which is the IP address of your computer. Your computer collects the packets and uses them to put together this article. Congrats, you just used the internet.
