What is Express.js architecture and how does it work?

Can you explain the architecture of Express.js?

Sure! Express.js is a minimal and flexible Node.js web application framework that provides a robust set of features for web and mobile applications. It follows a middleware architecture, where requests are processed through a series of middleware functions.

What are middleware functions in Express.js?

Middleware functions are functions that have access to the request and response objects. They can modify the request, end the response, or call the next middleware function in the stack.

How does routing work in Express.js?

Routing in Express.js is handled by defining routes using methods like app.get(), app.post(), etc. Each route can have multiple middleware functions that execute in order.

Can you give an example of a simple Express.js application?

Absolutely! A simple Express.js app might look like this:

const express = require('express');
const app = express();

app.get('/', (req, res) => {
  res.send('Hello World!');
});

app.listen(3000, () => {
  console.log('Server is running on port 3000');
});