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How the Web Works — Browsers & Servers

⏱️ 15 min
🌐 HTML5 Foundations

Welcome!

Learn how the internet works — DNS, HTTP, the client-server model, and what happens when you type a URL.

Who Talks to Whom

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Client
Your browser — Chrome, Firefox, Safari — requesting a page.
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Server
The computer hosting the website, waiting for requests.
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DNS
The internet's phone book — turns a domain name into an IP address.
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HTTPS
HTTP plus SSL encryption — keeps data private in transit.

HTTP Methods

  • GET — read data
  • POST — send/create data
  • PUT — update data
  • DELETE — delete data

What Happens When You Type google.com

The Request/Response Cycle
HTTP
// 1. DNS lookup → IP: 142.250.80.46
// 2. Browser sends HTTP request
GET / HTTP/1.1
Host: google.com
Accept: text/html

// 3. Server responds
HTTP/1.1 200 OK
Content-Type: text/html

<!DOCTYPE html>...
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Frontend vs Backend
Everything the browser renders and runs is "frontend" (HTML/CSS/JS in this course's first three modules); everything running on the server that the browser talks to is "backend" (Node/Express in later modules).
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