What Happens When You Type a URL?
The complete journey a request makes — before you see a single pixel
You type "radartrek.com" into your browser and hit Enter. Less than a second later, a page appears. What happened in between? This lesson maps the full journey — and gives you a mental model for everything else in this course.
The restaurant analogy
A website visit is like ordering in a restaurant
You (the browser) walk in and give your order to the waiter (the web server). The waiter takes your order to the kitchen (the application server), who checks the pantry (database) for the ingredients. The kitchen prepares your dish and the waiter brings it back to your table. You eat it (the browser renders the page). The whole process is invisible to you — but understanding the kitchen is what separates a website visitor from a web builder.
The five stages in plain English
- 1. DNS lookup — Your browser asks "what is the IP address of radartrek.com?" A DNS server looks it up — like calling directory enquiries for a phone number. Takes ~20ms.
- 2. TCP connection — Your browser dials the server using its IP address. They shake hands and establish a channel — like picking up the phone before you can speak.
- 3. HTTPS handshake — They agree on encryption so nobody can eavesdrop on the conversation. This is what the padlock means.
- 4. HTTP request and response — Your browser says "GET /about-us HTTP/1.1". The server returns the HTML file for that page.
- 5. Browser renders — The browser reads the HTML, fetches linked CSS and JS files, and builds the visual page you see. This is where HTML and CSS come in.
Why this matters for builders
Every decision you make as a web builder sits somewhere in this chain. Choosing a host affects steps 3 and 4. Writing efficient database queries affects step 4. Compressing images affects how quickly step 5 completes. Understanding the chain means you know where to look when something is slow or broken.
Open DevTools and watch it happen
In Chrome or Edge: press F12, click Network, refresh any page. You'll see every request the browser makes — the HTML, the CSS files, the images, the fonts. Each row is one request. Click on one and you can see the exact timing of each stage. This is one of the most useful developer tools you'll ever use.
Try this
Open browser DevTools (F12), go to the Network tab, visit any website, and find the first HTML request in the list. Look at the "Timing" section — you'll see DNS lookup, TCP connection, SSL handshake, and download time, all in milliseconds.