Why this lesson matters

Understand project structure and use it correctly in an App Router project. Next.js adds routing, server rendering, data boundaries and production build behavior around React; understanding the project tree prevents framework conventions from feeling magical.

How to reason about it

  • For Project Structure, the outcome to verify is: A folder represents a route segment and page.tsx supplies that route UI.
  • In Project Structure, keep this failure controlled: Treating Next.js as client-only React leads to unnecessary browser JavaScript and server/client boundary mistakes.
  • Project Structure practice target: Create a fresh App Router project and identify which files own a page, layout, configuration and public asset.
Diagram

Project layers

Practical walkthrough

In the Project Structure walkthrough: A folder represents a route segment and page.tsx supplies that route UI.

app/dashboard/page.tsxtsx
export default function DashboardPage() {
  return <main><h1>Dashboard</h1></main>;
}

Practice it yourself

Practice

Project Structure exercise

Create a fresh App Router project and identify which files own a page, layout, configuration and public asset.

  • Record the expected result before execution
  • Test one valid path and one lesson-specific failure path
  • Explain in two lines which boundary owns the decision

Summary