Free Next.js Course: Getting Started with Next.js

Learning the basics of Next.js 15 to build and deploy enterprise-grade SaaS applications

Next.js has revolutionized how developers build modern web applications. In this comprehensive course, we'll explore what makes Next.js special and how to get started with your first Next.js project.

What is Next.js?

Next.js is a powerful React framework that provides a robust foundation for building production-ready web applications. It extends React's capabilities by adding server-side rendering, static site generation, and an intuitive file-based routing system.

Next.js Key Features

Next.js enhances React development with:

  • Server-Side Rendering (SSR): Generates HTML on the server for improved performance and SEO
  • Static Site Generation (SSG): Pre-renders pages at build time for optimal loading speed
  • File-based Routing: Automatically creates routes based on your file structure
  • API Routes: Enables building API endpoints within your Next.js application
  • TypeScript Support: First-class TypeScript integration for type safety
  • Built-in Optimizations: Automatic image, font, and script optimization

What Apps is Next.js Good For?

Next.js excels in building various types of web applications:

E-commerce Platforms

Next.js's hybrid rendering capabilities make it perfect for e-commerce sites that need:

  • Fast page loads for product listings
  • SEO optimization for product pages
  • Dynamic cart and checkout functionalities

Content-rich Websites

Blogs, news sites, and documentation platforms benefit from:

  • Static generation for content pages
  • Incremental Static Regeneration for fresh content
  • Built-in image optimization

Web Applications

SaaS products and web apps leverage:

  • Server-side rendering for dynamic data
  • API routes for backend functionality
  • Client-side navigation for smooth user experience

Getting Started with Next.js

Let's create your first Next.js application using the latest version with TypeScript support.

Creating a New Next.js Application

Open your terminal and run:

npx create-next-app@latest my-nextjs-app --typescript

During setup, you'll be prompted with several options:

√ Would you like to use TypeScript? Yes
√ Would you like to use ESLint? Yes
√ Would you like to use Tailwind CSS? Yes
√ Would you like to use the `src/` directory? Yes
√ Would you like to use App Router? Yes
√ Would you like to customize the default import alias? No

This creates a new Next.js project with:

  • TypeScript configuration
  • ESLint setup
  • Tailwind CSS integration
  • Modern App Router architecture

Project Structure

After creation, your project structure will look like this:

my-nextjs-app/
├── src/
│   ├── app/
│   │   ├── layout.tsx
│   │   ├── page.tsx
│   │   └── globals.css
│   ├── components/
│   └── lib/
├── public/
├── next.config.js
├── package.json
├── tsconfig.json
└── tailwind.config.ts

Let's examine each key directory and file:

src/app Directory

The app directory is the heart of your Next.js application:

// src/app/layout.tsx
export default function RootLayout({
  children,
}: {
  children: React.ReactNode;
}) {
  return (
    <html lang="en">
      <body>{children}</body>
    </html>
  );
}
// src/app/page.tsx
export default function Home() {
  return (
    <main className="flex min-h-screen flex-col items-center justify-between p-24">
      <h1>Welcome to Next.js</h1>
    </main>
  );
}

Running Your Next.js Application

Start the development server:

npm run dev

Your application will be available at http://localhost:3000. Next.js includes:

  • Fast Refresh for immediate feedback
  • Development error overlay
  • Built-in TypeScript type checking

Anatomy of a Next.js Project Structure 🗂️

Let's dive deep into the architecture of a Next.js application! Understanding the project structure is crucial for building scalable and maintainable applications.

Core Directories and Their Purpose

A Next.js project is organized into several key directories, each serving a specific purpose in your application's architecture. Let's explore each one:

my-nextjs-app/
├── src/
│   ├── app/        # App Router pages and API routes
│   ├── components/ # Reusable UI components
│   └── lib/        # Utility functions and shared logic
├── public/         # Static assets
├── next.config.js  # Next.js configuration
├── package.json    # Project dependencies
├── tsconfig.json   # TypeScript configuration
└── tailwind.config.ts # Tailwind CSS configuration

The src/app Directory Deep Dive

The app directory is the cornerstone of your Next.js application. It uses the new App Router conventions for routing and layouts:

src/app/
├── layout.tsx      # Root layout (applied to all pages)
├── page.tsx        # Homepage route
├── about/
│   └── page.tsx    # /about route
├── blog/
│   ├── layout.tsx  # Blog-specific layout
│   ├── page.tsx    # /blog route
│   └── [slug]/     # Dynamic blog post routes
│       └── page.tsx
└── api/           # API routes
    └── hello/
        └── route.ts

💡 Key Insight: The file system is your routing system! Each page.tsx automatically becomes a route in your application.

Understanding Special Files

Next.js includes several special files that enhance your application's functionality:

// src/app/layout.tsx - Root Layout
export default function RootLayout({
  children,
}: {
  children: React.ReactNode;
}) {
  return (
    <html lang="en">
      <body className="min-h-screen bg-background">
        <header>
          {/* Shared navigation */}
        </header>
        {children}
        <footer>
          {/* Shared footer */}
        </footer>
      </body>
    </html>
  );
}
// src/app/loading.tsx - Loading UI
export default function Loading() {
  return (
    <div className="flex items-center justify-center min-h-screen">
      <div className="animate-spin rounded-full h-32 w-32 border-b-2 border-primary" />
    </div>
  );
}
// src/app/error.tsx - Error Boundary
'use client';
export default function Error({
  error,
  reset,
}: {
  error: Error;
  reset: () => void;
}) {
  return (
    <div className="flex flex-col items-center justify-center min-h-screen">
      <h2>Something went wrong!</h2>
      <button onClick={reset}>Try again</button>
    </div>
  );
}