Project structure overview in NextJS - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of the app directory in a Next.js 14 project?

The app directory holds the main application code using the new App Router. It organizes pages, layouts, and server components in a nested folder structure.

beginner

What role does the public folder play in a Next.js project?

The <code>public</code> folder stores static files like images, icons, and fonts. These files are served directly at the root URL and do not require import statements.

beginner

Why is the node_modules folder important in Next.js projects?

The node_modules folder contains all installed packages and dependencies needed for the project to run. It is managed automatically by the package manager.

intermediate

What is the function of the next.config.js file?

The next.config.js file is used to customize and configure Next.js settings like routing, image optimization, and environment variables.

beginner

How does the package.json file support a Next.js project?

The package.json file lists project metadata, scripts, and dependencies. It helps manage packages and defines commands like npm run dev to start the development server.

Which folder in Next.js 14 contains the main app code using the App Router?

A public

B pages

C app

D components

The app folder is the new main directory for routing and components in Next.js 14.

Where should you put images that need to be served directly without import in Next.js?

A public

B components/assets

C app/images

D styles

Static files like images go into the public folder to be served directly.

What file do you edit to change Next.js configuration settings?

A next.config.js

B package.json

C app/layout.js

D README.md

The next.config.js file is for customizing Next.js settings.

Which file lists the dependencies and scripts for a Next.js project?

A public/index.html

B next.config.js

C app/page.js

D package.json

The package.json file manages dependencies and scripts.

What is the purpose of the node_modules folder?

A To hold static images

B To store installed packages and dependencies

C To write page components

D To configure environment variables

The node_modules folder contains all installed packages needed for the project.

Describe the main folders and files you find in a Next.js 14 project and their purposes.

Think about where code, static files, and settings live.

Explain how the app directory differs from the old pages directory in Next.js.

Focus on routing and layout differences.

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