TL;DR: Most developers I've talked to can describe HTTP abstractly — "the browser sends a request, the server sends back HTML" — but freeze up when a real problem hits. A CORS error shows up and they paste it into Stack Overflow without understanding why two different origins are eve 📖 Reading time: ~45 min What's in this article You've Typed a URL a Million Times — But Do You Know What Happens Next? Step 1: You Hit Enter — Your Browser Does Not Know Where to Go Yet Step 2: DNS — The Phone Book Nobody Talks About Clearly Your Browser Has No Idea Where GitHub Lives — Until It Asks Step 3: TCP Handshake — Before Any Web Data Moves, a Connection Has to Open Three Messages, One Goal: Prove You Both Exist Step 4: TLS — The Padlock in Your Address Bar, Demystified What TLS Actually Does (And Why You Should Care) You've Typed a URL a Million Times — But Do You Know What Happens Next?…