Prashant Lakhera
3 min readMar 11, 2024

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📌 21 Days of DevOps Interview — Day 11 -What will happen when you type www.google.com on browser📌

Have you ever wondered what happens when you type www.google.com into your browser? Let’s break down these complexities into simple terms.

1️⃣ DNS Resolution: First, your browser looks for the IP address linked to “www.google.com" in its local DNS cache. If it’s not there, it fires a query to a DNS resolver.
2️⃣ TCP Handshake: Next, your browser reaches out to Google’s server through a TCP handshake. Think of it as a secret handshake, ensuring a reliable connection between your browser and the server.
3️⃣ SSL/TLS Handshake: This ensures your data is encrypted, safeguarding your information.
4️⃣ HTTP Request: Your browser politely asks the server for the webpage using an HTTP GET request. This request includes all necessary details, such as language preference and device information.
5️⃣ Server Processing: The server processes your request, which could involve database queries, script executions, or retrieving stored data.
6️⃣ HTTP Response: The server then responds with the webpage content, packaged with an HTTP status code and headers.
7️⃣ Content Rendering: Your browser receives this and begins parsing HTML, applying CSS, and executing JavaScript to display the webpage just right.
8️⃣ Asynchronous Tasks: Meanwhile, your browser performs background tasks to fetch additional data or update the page dynamically without reloading.
9️⃣ Browser Caching: Browsers store resources from webpages to display content even faster next time.
🔟 Content Rendering: The browser finalizes rendering the page, ensuring everything looks as it should.
1️⃣1️⃣ User Interaction: Now, it’s your turn to interact with the fully loaded page, whether clicking links, filling out forms, or scrolling.
1️⃣2️⃣ Continuous Updating: Some pages continuously update with new information (like live scores or news), keeping you informed in real-time.
1️⃣3️⃣ Session Management: Cookies personalize your browsing session and keep track of your preferences and login sessions.
1️⃣4️⃣ Persistence: The browser ensures a speedy return visit by caching resources.
1️⃣5️⃣ Security: Your browser checks certificates and guards against web threats.
1️⃣6️⃣ Error Handling: Your browser guides you with error messages or redirections if anything goes wrong.

🎬 It’s a whole journey from typing a URL to viewing a webpage, involving DNS lookups, secure handshakes, data requests, and the transformative rendering of content. Understanding these underlying processes gives us a greater appreciation for daily seamless browsing experiences.

📚 If you’re interested in more in-depth explanation of these topics, please check out my new book “Cracking the DevOps Interview”

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Prashant Lakhera

AWS Community Builder, Ex-Redhat, Author, Blogger, YouTuber, RHCA, RHCDS, RHCE, Docker Certified,4XAWS, CCNA, MCP, Certified Jenkins, Terraform Certified, 1XGCP