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

The article traces a web request from a browser button click through `fetch()` and into an Express server.

On the server, middleware processes the HTTP request first, then the route handler passes control to application logic and the controller.

From there, the backend may query the database and send a JSON response back to the browser.

Understanding this end-to-end flow helps developers debug requests and connect frontend actions to backend code and storage.