React is fantastic for building interactive user interfaces. It lets us create reusable components that manage their own state, making complex applications easier to handle. However, a standard React app does most of its work in the user's browser. This is called client-side rendering. The browser gets a nearly empty HTML file and some JavaScript, then React kicks in to build the page. This can lead to a slight delay before the user sees any content and can make it harder for search engines to index your site.

This is where Next.js comes in. It's a framework built on top of React that solves these problems by enabling rendering on the server. Instead of sending an empty shell to the browser, Next.js can pre-render the page on the server and send fully formed HTML. This means the user sees the content almost instantly.

It does this through two main strategies: Server-Side Rendering (SSR) and Static Site Generation (SSG).

• Server-Side Rendering (SSR): With SSR, the server generates the HTML for the page each time a user requests it. This is perfect for pages that display dynamic, frequently changing data, like a social media feed.
• Static Site Generation (SSG): With SSG, the HTML is generated once at build time, when you deploy your app. The resulting files can be hosted on a global CDN, making them incredibly fast to load. This is ideal for content that doesn't change often, like a blog post or a marketing page.

Starting a new Next.js project is simple thanks to a command-line tool. You'll need to have Node.js installed on your computer. Once that's ready, open your terminal and run the following command. It will ask you a few questions to configure your project, like whether you want to use TypeScript and Tailwind CSS. For now, you can stick with the defaults.

After the command finishes, you'll have a new folder with your project's name. Inside, you'll find a few files and folders, but the most important one for now is the app directory. This is where the core of your application will live.

One of the most powerful features of Next.js is its routing system. If you've used React before, you might have used a library like React Router to declare your routes in code. Next.js simplifies this dramatically.

Routing is based entirely on the file and folder structure inside the app directory. To create a new page, you simply create a new folder and add a page.js (or .tsx) file inside it. The path to that file becomes the URL for the page.

For example:

• app/page.js corresponds to the homepage, or the / route.
• app/about/page.js creates an /about route.
• app/products/shoes/page.js creates a /products/shoes route.

This convention removes the need for manual route configuration, making your project easier to navigate and understand. Any React component exported from a page.js file will be rendered as a page at its corresponding URL.

This just scratches the surface of what Next.js can do. By handling rendering on the server and providing a simple yet powerful routing system, it sets a strong foundation for building modern web applications.