Node.js is a runtime environment that allows you to run JavaScript on the server side. It is built on Chrome's V8 JavaScript engine and is known for its non-blocking, event-driven architecture, which makes it efficient and suitable for building scalable network applications.

Basics of Node.js and Backend Development

NPM (Node Package Manager)

NPM is the default package manager for Node.js and is used to manage dependencies in your projects. With NPM, you can easily install and update libraries and tools that you use in your application. It also helps in managing versioning and sharing code with other developers.

Express.js

Express.js is a minimal and flexible Node.js web application framework that provides a robust set of features to develop web and mobile applications. It simplifies the process of building server-side logic and handling HTTP requests. With Express, you can create routes to handle different endpoints and use middleware to manage the flow of data through your application.

Setting Up a Simple Node Server with Express

To set up a simple Node server using Express, follow these steps:

1. Initialize a new project:

   npm init -y
   
   

2. Install Express:

   npm install express
   
   

3. Create a server file (e.g., server.js):

   const express = require('express');
   const app = express();
   const port = 3000;
   
   app.get('/', (req, res) => {
     res.send('Hello World!');
   });
   
   app.listen(port, () => {
     console.log(`Server is running on <http://localhost>:${port}`);
   });
   
   

4. Run the server:

   node server.js
   
   

With these basics, you can start building more complex backend applications using Node.js and Express.js, handling various routes, integrating databases, and adding more advanced features as needed.