In this post, we'll be looking at Node.js and Express.js, two popular tools used for software development.
Node.js is a JavaScript runtime environment that allows you to run JavaScript code outside of a browser. This makes it ideal for developing server-side applications.
Express.js is a web application framework for Node.js. It provides a set of tools for building web applications.
Node.js is a JavaScript runtime environment that allows you to run JavaScript code outside of a browser. This makes it ideal for developing server-side applications.
Node.js is based on the V8 JavaScript engine, which is used in Google Chrome. Node.js also has a large ecosystem of open-source libraries that can be used for various tasks.
Installing Node.js is a simple process. You can download the Node.js installer from the Node.js website.
Once the installer has been downloaded, run it and follow the instructions. Node.js will be installed on your computer.
Once Node.js has been installed, you can run JavaScript code using the Node.js runtime.
To run a JavaScript file, use the following command:
node {filename}
For example, to run a file named hello.js, you would use the following command:
node hello.js
Node.js will execute the code in the hello.js file and print the results to the console.
Express.js is a web application framework for Node.js. It provides a set of tools for building web applications.
Express.js is a popular choice for building web applications. It is easy to use and has a large community of users.
Let's create a simple "Hello, World!" application using Express.js.
Create a file named hello.js and add the following code:
const express = require('express');
const app = express();
app.get('/', (req, res) => {
res.send('Hello, World!');
});
app.listen(3000, () => {
console.log('Hello, World! app is listening on port 3000');
});
This code creates an Express.js application that responds to HTTP GET requests with a "Hello, World!" message.
The app.listen() method starts the Express.js application on port 3000.
To run the application, use the following command:
node hello.js
You can now access the application at http://localhost:3000.
In this post, we've looked at Node.js and Express.js. We've seen how to install Node.js and run JavaScript code using the Node.js runtime. We've also seen how to create a simple web application using Express.js.