What really happens when you type www.example.com?

We’ve all heard the question in interviews.
Seems simple, right?

But under the hood, it’s layers of engineering magic—and honestly, it’s one of the best ways to appreciate the full stack of how the internet works.

From keystroke to page load, here’s a whirlwind view:
1. Your browser checks its cache
2. DNS resolution kicks in (Is www.example.com an IP I know?)
3. System resolver queries your local DNS server
4. A TCP connection is opened (3-way handshake)
5. Then, TLS/SSL handshake for HTTPS
6. Your browser sends an HTTP request
7. Google’s server responds, often via a CDN
8. Your browser parses HTML, fetches JS/CSS, renders the page
9. Meanwhile, cookies, cache, and compression all come into play
10. All this happens in milliseconds

And that’s the super simplified version.

The alex/what-happens-when GitHub repo breaks this down brilliantly, including:
• DNS resolution details
• OSI layers
• CDN routing
• Browser rendering
• And even power consumption!

It’s a rabbit hole every engineer should explore at least once.

⸻

Whether you’re into DevOps, SRE, networking, or frontend—this question ties it all together.

If you haven’t read it yet, bookmark this:
https://lnkd.in/dgvSdTVz

Curious: What part of this process do you find most fascinating—or challenging to explain?