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Popular interview question: What happens when you type google .com into a browser? 1 - First up, you type the website address in the browser’s address bar. 2 - The browser checks its cache first. If there’s a cache miss, it must find the IP address. 3 - DNS lookup begins (think of it as looking up a phone number). The request goes through different DNS servers (root, TLD, and authoritative). Finally, the IP address is retrieved. 4 - Next, your browser initiates a TCP connection like a handshake. For example, in the case of HTTP 1.1, the client and server perform a TCP three-way handshake with SYN, SYN-ACK, and ACK messages. 5 - Once the handshake is successful, the browser makes an HTTP request to the server and the server responds with HTML, CSS, and JS files. 6 - Finally, the browser processes everything. It parses the HTML document and creates DOM and CSSOM trees. 7 - The browser executes the JavaScript and renders the page through various steps (tokenizer, parser, render tree, layout, and painting). 8 - Finally, the webpage appears on your screen. Over to you: Which other step will you add to the overall process? -- Subscribe to our weekly newsletter to get a Free System Design PDF (158 pages): bit.ly/bbg-social