What is a Next js

Next.js is an open-source framework built on Node.js that allows you to create React applications that you can render on the server. It provides out-of-the-box tooling and configuration you need to build fast, SEO-friendly React apps.

Whether you want to create static pages, e-commerce applications, or fetch data from APIs, Next.js can help. It enables you to go from one line of code to a full-blown application with little configuration.

This is the main advantage of Next.js. Once you install it, you can start creating fast production-ready applications.

Benefits of Using Next.js

1) Shallow Learning Curve.

Next.js is a React wrapper which means it extends React's code syntax. React developers can therefore pick it up quite easily. And like React, Next.js has the create-next-app command that you can execute to scaffold a new Next app quickly.

Run the following command in the terminal, and Next.js, will install the necessary packages and create the files to get you started.

2) Pre-Rendering

JavaScript frameworks like React, Angular, and Vue popularized client-side rendering. This is a rendering method where the server sends the HTML shell and a JavaScript bundle. That code then runs in the browser, updating the document in a process called hydration.

Since rendering happens on the user's device, CSR applications can be slow. Next.js provides a solution through pre-rendering. Instead of building the UI on the client side, Next.js builds it in advance on the server.

There are two types of pre-rendering:

Server-side rendering (SSR)

Static Site Generation (SSG)

3) Built-In Routing

Next.js uses a file-based routing system. The server automatically converts all the files saved in the Pages folder to routes. This is unlike React applications that require installing React router and configuring it.

Furthermore, React supports client-side routing through the <Link/> component. It also prefetches the pages whose links are in the viewport. This is only for pages using SSG, but even then, this feature makes navigating from one page to another seem very fast.

4) Automatic Code Splitting

Code splitting refers to dividing the bundle files into chunks that you can lazy load on demand. Next.js automatically handles code splitting. Next.js automatically splits each file in the Pages folder into its own bundle. Additionally, any code shared between the pages is bundled into one to prevent downloading the same code.

Code splitting reduces the initial load time since the browser has to download only a small amount of data.

5) Built-In Image Optimization

Heavy images can slow down your site and lower its Google rankings. With Next.js, you can use the image component to optimize images automatically.

import Image from 'next/image'

This component serves correctly sized images and modern formats like webp if the browser supports it. Images are also loaded only when a user scrolls them into view. This optimizes the page speed and saves space on the user's device.

6) Built-In CSS Support

Next.js supports CSS modules and Sass out of the box. You don't need to spend extra time configuring it and can go straight to writing CSS styles. Next.js also comes with styled-jsx which allows you to write CSS directly inside your component.

7) Growing Community

Since Next.js is built on React, it is gaining popularity quite fast. There is, therefore, a growing community of developers willing to help if you get stuck. This, combined with excellent documentation, ensures that even beginners can easily get started with Next.js.

When Should You Use Next.js?

One of the best things about Next.js is its rendering options. You are not tied to CSR, SSR, or SSG and can choose which pages you want to render on the server side, or client side, or which ones you want to be entirely static.

Because of this, you can customize how each page in your application renders based on its needs. For instance, you can render pages that rely on constantly changing data using SSR and render a static page like the login page using SSG.

Next.js comes with many built-in features and extra configuration that allows you to start adding features right away. You don't need to worry about configuring your app's routes, optimizing images, or splitting bundle files. It's all done for you.

If you want to create React applications that consume dynamic content and don't want to spend time setting things up, installing packages, or configuring your application to be fast, Next.js is the best solution. However, if you're creating a static single-page app, plain React is still a good option.