What Actually Happens When You Click a Button — From Browser to Database and Back

You've written fetch() . You've set up an Express route. It works. But do you actually know what happened in between? Most tutorials show you the pieces separately. Nobody walks you through the full conversation — browser to server to database and back — in one go. Let's fix that. The analogy that makes it click Before we touch code, here's a mental model you'll never forget. Think of it like ordering food at a restaurant: You (the customer) = the browser The waiter = the Express server / API Th