vasanthk/how-web-works

This is an educational document that walks you through everything that happens, step by step, when you type a web address like google.com into your browser and press Enter. What seems like a simple action actually involves dozens of complex processes happening in fractions of a second. The journey starts the moment you press a key on your keyboard, which sends electrical signals through USB or Bluetooth to your computer. Your browser then interprets the URL you typed, figures out whether it should use regular HTTP or secure HTTPS, and looks up the numeric internet address (IP address) for the website you want. This lookup checks multiple caches in sequence, your browser, your operating system, your router, and your internet provider, before doing a full search across the internet's address system if needed. Once it has the destination address, your browser opens a connection to the web server and performs a security handshake to set up encrypted communication. It then sends a request for the page, and the server sends back the HTML content. The browser doesn't just display raw text though, it parses the HTML into a structured tree of elements, processes the styling rules, figures out where everything should be positioned on screen, and paints the final result you see. The document covers each of these stages in plain detail: DNS lookups, TCP connections, HTTP requests and responses, and how browsers render pages from raw code into the visual result you see. This is a great reference for anyone curious about the hidden machinery of the web, explained without assuming deep technical knowledge.