How the Internet Actually Works
A 5-minute explanation to leave you less confused about what happens behind your screen.
There are over 1.5 billion websites in existence [1]. 1,500,000,000. Where do they sit?
What about all the data we create? Over 350 million photos are posted on Facebook [2]. Not per year. Not per month. Per day.
350,000,000 photos every day.
Where’s it stored? How can we access it so quickly from a device in our hands?
The internet isn’t widely understood, and this misinformation is one of the root causes of privacy violations, scams, and general difficulty navigating the internet.
The internet is a network of computers, like ours, that send messages to each other through devices called routers. In this article, I’ll break down the basics of the internet so you can understand what’s going on without any computer knowledge. You’ll see how computers communicate and what happens behind the scenes when you visit a website like Facebook.
With this information, you’ll feel less confused about the inner workings of the internet. You’ll also have a solid foundation so you can build up any extra knowledge you need in specific areas of this technology which has allowed us to see cat videos and bravely insult each other anonymously, all from the comfort of our homes.
What the internet is made of
Unlike a company with a headquarters, there is no central control unit for the internet. Instead, the internet exists thanks to distributed networking; computers all around the world connect to each other by transmitting and receiving data, and this network of talking computers forms the internet.
You can think of these computers as a city. Each computer which connects to the rest is given its own address. This address is known as the IP address. An IP looks like 69.63.181.15. Not very readable.
We don’t deal with IP addresses, but domains. Domains are the human-friendly way of navigating the internet, such as https://medium.com/@basselghazali
A functioning website is made possible thanks to a computer at a specific IP. This computer “hosts” the website, meaning it sends the website content (text, images, etc.) whenever people request it.
Since we don’t type IP addresses — but rather domains — the computer also needs a registered domain which links the website name to the computer’s IP, so that we can type an understandable website name and be directed to this computer.
The domain name-to-IP translation happens using the Domain Name System (DNS). Think of it as a map which tells you what IP to go to when you give it a domain name. DNS mapping is a service offered by different companies such as Google or your ISP.
How do these connected computers let us browse the internet?
Our computers connect to the internet with the help of devices called routers, which connect our devices to the Internet Service Provider (ISP) we pay, such as Virgin Media or AT&T. This company then facilitates our communication with the rest of the network.
Since we’re saying the internet is just connected computers, does this mean that when I visit Facebook, I’m talking to one of their computers?
Yes. But it’s not Zuckerberg’s laptop.
Most websites and companies use servers to handle the requests they get. A server is a specialised computer, whose job is to be available all the time to respond to people’s requests by sending back the information they need (in this case, the website data).
What happens behind the scenes when we type in a website?
If you wanted to open Medium on your phone: you would go to the browser, type in the website, hit enter, and you’re there.
Behind the scenes:
- Your phone sent a request to your ISP to find the IP related to Medium’s website.
- Your ISP located Medium’s server using the DNS mapping of medium.com
- A request was sent to Medium’s server.
- The server responded with the content of its website
- Your phone displayed that content to you.
If Medium’s servers were to shut down, your phone wouldn’t get the webpage data and it wouldn’t be able to show you the website.
Let’s say you then decide you’re tired of reading, and you want to watch videos of cats on YouTube instead. You type the website, hit enter, and you’re shown the YouTube home page. Behind the scenes, a request was sent to YouTube’s server, which is in a completely different IP from Medium’s. The server then sends back the webpage data, and your phone can display it, and you can spend the next 3 hours saying “just one more video”.
Note: we imagined it’s the ISP providing the DNS service in these examples; the order of operations would’ve been the same if we used another service, we just would have gone to the DNS server directly instead of going through the ISP.
The difference between a safe and unsafe connection
What we see on our screens is not exactly what computers communicate with each other. A set of “languages” was established for all devices to use and communicate over the internet. These languages are called protocols, and the most common one is HTTP.
It’s not important to understand the details of these protocols, but one important distinction to make is between HTTP and HTTPS.
A website with an HTTP connection starts with http://
These connections are not secure. Since most devices can understand HTTP, anyone who intercepts an HTTP signal you send out can see its contents. This means they can access potentially sensitive information such as passwords you entered. Be wary of giving sensitive data to such sites.
On the other hand, when you see a website which starts with https://, it means the connection is secure; your device sends the data locked (encrypted) in a way which only the intended recipient can unlock (decrypt) it. This means that if someone else’s device were to get that data, they wouldn’t be able to understand anything and your privacy is maintained.
A device that wants to communicate via HTTPS also has to prove its identity, which means you’re sure the server is who it claims to be.
P.S. This doesn’t mean that every website with HTTPS is safe, beware of scams, research the websites you visit, and ask for a second opinion if you’re unsure of their legitimacy.
Wrapping up
Knowing how the internet works should let you confidently navigate the digital world and make informed decisions about your data. It makes it easier to spot potential privacy violations, scams, and other malicious actors on the internet so you can keep your data safe and secure.
I hope your new understanding of where websites come from helps you feel more in control of your digital experience.
Does this new information lead you to any other questions about the internet? If so, drop them in the comments, I’d love to help clear up any uncertainty!
References
- Internet Live Stats https://www.internetlivestats.com/total-number-of-websites/
- A Focus On Efficiency, A whitepaper from Facebook, Ericsson and Qualcomm September 16 2013, https://www.scribd.com/document/468786966/White-Paper-Facebook-Ericsson-qualcomm-pdf#
