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What if your components could talk to the database directly?

They can, and most of yours already do. Every component in the App Router starts on the server, so it can call the API, read the database, hold the key, and finish its work before the page reaches your visitor. The browser gets the result, not the work.

What if the page didn’t wait for its slowest part?

It doesn’t have to. The static shell ships first, and each slow part leaves a fallback in its place. When a part finishes on the server, its HTML streams down the same response and takes the fallback’s place. The fast parts never wait for the slow ones, whatever they sit next to.The three rows below are slow on purpose, with their delays printed on them.

What if the form just called the function?

It does now. A Server Action runs on the server and plugs straight into a form’s action: no endpoint to design, no fetch to write, no JSON contract to keep in sync. Add one to the count and follow it: the form calls the function, the function writes the new count, and Next.js re-renders the page around it.

What actually happens when you press +1?

A component is a function. Render means React calls it and paints what it returns, so a value that has to survive from one call to the next needs somewhere to live in between. useState is that place. The setter does two jobs: it stores the new value where React keeps it, and it schedules the next call, the render that paints it.Press +1 and the number moves, the way counters always have.