2. How the Internet Works

Foundation

You use the internet every day — but do you actually know what happens when you type google.com and press Enter? Understanding this is not optional for a developer. Almost everything you will build lives on the internet. Knowing how data travels gives you an enormous advantage when things break — and things will break.

The Internet vs. The Web — Not the Same Thing

Most people use these words interchangeably. They are completely different things:

The Internet

The global physical infrastructure — undersea cables, routers, satellites, and data centres — that connects billions of devices. It is the hardware layer.

The World Wide Web (Web)

A system of web pages and apps that runs ON TOP of the internet using HTTP. Email, Zoom calls, and WhatsApp messages also use the internet but are not the web.

What Happens When You Type a URL

When you type https://learn.voidxhq.com and press Enter, here is exactly what happens in under 300 milliseconds:

DNS Lookup: Your browser asks a DNS (Domain Name System) server: "What is the IP address of learn.voidxhq.com?" DNS is the internet's phone book — it translates human-readable names into numerical IP addresses like 104.21.55.178.
TCP Connection: Your browser connects to that IP address over the internet. A TCP handshake confirms both sides are ready to communicate.
HTTPS / TLS Handshake: Because the URL starts with https://, your browser and the server agree on an encryption key. All data is now encrypted — no one in the middle can read it.
HTTP Request: Your browser sends a request: GET me the content at the path /. The server receives this.
Server Response: The server sends back HTML, CSS, and JavaScript files — the raw code that makes the page.
Rendering: Your browser reads the HTML, applies CSS styles, runs JavaScript, and paints the visual page on your screen.

Clients and Servers

The internet runs on a client-server model. Understanding this model is the foundation of all web development:

Client

Your browser, your phone app, your laptop. The client makes requests — give me this page, log me in, show me my profile.

Server

A computer in a data centre (like AWS or Google Cloud) that receives requests, processes them, and sends back responses. It runs 24/7.

API

The agreed-upon language clients and servers use to talk. When your Instagram app loads photos, it calls Instagram's API — which returns data the app turns into a visual feed.

HTTP Methods — The Vocabulary of the Web

When your browser (client) talks to a server, it uses HTTP methods to express intent. These four are the foundation of every web interaction you will ever build:

GET

Retrieve data. Loading a webpage, fetching a user's profile, getting a list of products. Read-only — GET should never change anything.

POST

Send data to create something new. Submitting a form, creating an account, posting a tweet.

PUT / PATCH

Update existing data. Editing your profile name, updating a post, changing a setting.

DELETE

Remove data. Deleting your account, removing a file, cancelling a subscription.

Every time you interact with any website or app — scrolling, clicking, submitting, uploading — you are triggering HTTP requests behind the scenes. Developer tools in your browser (press F12) let you watch every single one in real time.

HTTP vs HTTPS

HTTP sends data in plain text — anyone between you and the server (your ISP, a hacker on the same Wi-Fi, a government router) can read it. HTTPS encrypts everything using TLS. The padlock icon in your browser confirms HTTPS is active. As a developer, every application you build must use HTTPS — never HTTP. Browsers now actively warn users about non-HTTPS sites.