Project structure overview in NextJS - Mini Project: Build & Apply

Next.js Project Structure Overview

📖 Scenario: You are starting a new Next.js project to build a simple website. Understanding the project structure helps you organize your files and code properly.

🎯 Goal: Learn the basic Next.js project structure by creating the main folders and files needed for a simple app.

📋 What You'll Learn

Create the app folder as the main directory for pages

Add a page.tsx file inside app with a simple component

Create a layout.tsx file inside app to define the page layout

Add a globals.css file inside app for global styles

💡 Why This Matters

🌍 Real World

Next.js projects use this structure to organize pages, layouts, and styles for scalable web apps.

💼 Career

Understanding Next.js project structure is essential for frontend developers working with React and modern web frameworks.

1

Create the app folder and page.tsx file

Create a folder named app and inside it create a file named page.tsx. In page.tsx, write a React functional component called Page that returns an <h1> with the text Welcome to Next.js.

NextJS

// Create the app folder and inside it create page.tsx
// Write a React functional component named Page that returns Welcome to Next.js

Hint

Use export default function Page() and return an <h1> element with the exact text.

2

Add a layout.tsx file inside app

Inside the app folder, create a file named layout.tsx. Write a React functional component called RootLayout that accepts a children prop of type React.ReactNode and returns an <html> element containing a <body> that renders the children.

NextJS

export default function Page() {
  return Welcome to Next.js;
}

// Create layout.tsx with RootLayout component that wraps children in  and 

Hint

Define RootLayout with a children prop and wrap it inside <html lang="en"> and <body>.

3

Create a globals.css file for global styles

Inside the app folder, create a file named globals.css. Add a CSS rule that sets the body background color to #f0f0f0 and the font family to Arial, sans-serif.

NextJS

export default function RootLayout({ children }: { children: React.ReactNode }) {
  return (
    
      {children}
    
  );
}

/* Create globals.css with body background and font styles */

Hint

Write CSS inside globals.css to style the body background and font.

4

Import globals.css in layout.tsx

At the top of the layout.tsx file inside app, add an import statement to import ./globals.css so the global styles apply to the app.

NextJS

// Import globals.css at the top of layout.tsx
export default function RootLayout({ children }: { children: React.ReactNode }) {
  return (
    
      {children}
    
  );
}

/* globals.css */
body {
  background-color: #f0f0f0;
  font-family: Arial, sans-serif;
}

Hint

Use import './globals.css'; at the top of layout.tsx.

Practice

1. What is the main purpose of the app/ folder in a Next.js project?

easy

A. To organize pages, layouts, and API routes

B. To store static files like images and fonts

C. To hold configuration files like next.config.js

D. To keep test files and mocks

Solution

1. Step 1: Understand the role of app/ folder

   The app/ folder is designed to organize the main parts of the app such as pages, layouts, and API routes.

2. Step 2: Compare with other folders

   The public/ folder holds static files, and config files are outside app/. So, app/ is for app structure.

3. Final Answer:

   To organize pages, layouts, and API routes -> Option A

4. Quick Check:

   app/ folder = organize pages/layouts/API [OK]

Hint: Remember: app/ is your app's main structure folder [OK]

Common Mistakes:

• Confusing app/ with public/
• Thinking config files go inside app/
• Assuming app/ holds only pages, ignoring layouts and APIs

2. Which folder should you place an image file in a Next.js project to serve it statically?

easy

A. app/

B. api/

C. components/

D. public/

Solution

1. Step 1: Identify static file storage

   Static files like images should be placed in the public/ folder so they can be served directly.

2. Step 2: Exclude other folders

   app/ is for pages/layouts, components/ is for React components, and api/ is for backend routes, so none are for static files.

3. Final Answer:

   public/ -> Option D

4. Quick Check:

   Static files = public/ folder [OK]

Hint: Static files go in public/ folder, not app/ [OK]

Common Mistakes:

• Putting images inside app/ folder
• Confusing components/ with static file storage
• Trying to serve images from api/ folder

3. Given this Next.js project structure:

app/
  layout.js
  page.js
public/
  logo.png

Which statement is true about accessing logo.png in the browser?

medium

A. You can access it at /logo.png

B. You must import it in page.js to use it

C. It is not accessible because it's inside public/

D. You can access it at /app/logo.png

Solution

1. Step 1: Understand public/ folder behavior

   Files in public/ are served at the root URL path, so logo.png is accessible at /logo.png.

2. Step 2: Check other options

   Importing is optional for static files; app/ folder files are not served as static assets, so /app/logo.png is invalid.

3. Final Answer:

   You can access it at /logo.png -> Option A

4. Quick Check:

   public/ files = root URL access [OK]

Hint: Static files in public/ map to root URL path [OK]

Common Mistakes:

• Thinking you must import static files to access them
• Trying to access static files via /app/ path
• Assuming public/ files are not accessible

4. You see this error in your Next.js app: "Module not found: Can't resolve './logo.png'". Your project has logo.png inside public/. What is the likely cause?

medium

A. You placed logo.png inside app/ instead of public/

B. You tried to import logo.png from public/ using a relative path

C. The logo.png file is missing from public/

D. Next.js does not support PNG images

Solution

1. Step 1: Understand how to use files in public/

   Files in public/ are accessed via URL paths, not imported with relative paths in code.

2. Step 2: Identify the error cause

   Trying to import logo.png with a relative path causes "Module not found" error because public/ files are not part of the module system.

3. Final Answer:

   You tried to import logo.png from public/ using a relative path -> Option B

4. Quick Check:

   Importing public/ files = error [OK]

Hint: Don't import public/ files; use URL paths instead [OK]

Common Mistakes:

• Importing static files from public/ folder
• Assuming public/ files are part of module imports
• Thinking Next.js can't serve PNG images

5. You want to create a new page with a custom layout in your Next.js app. Where should you place the layout and page files to follow the recommended project structure?

hard

A. Place both files inside components/ folder

B. Put layout.js in public/ and page.js in app/

C. Place both layout.js and page.js inside a new folder under app/

D. Put page.js in app/ and layout.js in api/

Solution

1. Step 1: Recall Next.js app folder structure

   In Next.js, pages and their layouts are organized inside folders under app/ to group related files.

2. Step 2: Exclude incorrect placements

   public/ is for static files, components/ is for reusable UI parts, and api/ is for backend routes, so these are not correct for layouts/pages.

3. Final Answer:

   Place both layout.js and page.js inside a new folder under app/ -> Option C

4. Quick Check:

   Layouts and pages live together under app/ [OK]

Hint: Keep layouts and pages together inside app/ folders [OK]

Common Mistakes:

• Putting layouts in public/ or api/
• Separating layout and page files into unrelated folders
• Confusing components/ with page structure