Express installation and setup - Cheat Sheet & Quick Revision

Recall & Review

beginner

What command do you use to create a new Node.js project before installing Express?

You use npm init -y to quickly create a new Node.js project with default settings.

beginner

How do you install Express in your project?

Run npm install express in your project folder to add Express as a dependency.

beginner

What is the basic code to create an Express app and start a server on port 3000?

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

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

app.listen(3000, () => {
  console.log('Server running on http://localhost:3000');
});
```

beginner

Why do we use app.listen() in Express?

app.listen() tells Express to start the server and listen for requests on a specific port.

beginner

What file usually contains the Express app setup code?

Typically, the main file is named index.js or app.js where Express is set up and the server starts.

Which command installs Express in your Node.js project?

A express install

B npm start express

C node install express

D npm install express

The correct command is npm install express to add Express to your project.

What does app.listen(3000) do in an Express app?

A Creates a new route

B Stops the server

C Starts the server on port 3000

D Installs Express

app.listen(3000) starts the server and listens for requests on port 3000.

Which file is commonly used to write Express setup code?

A style.css

B index.js

C package.json

D README.md

index.js or app.js usually contain the Express app setup code.

What is the purpose of npm init -y before installing Express?

A Creates a new Node.js project with default settings

B Installs Express globally

C Starts the Express server

D Updates npm to latest version

npm init -y quickly creates a new Node.js project with default settings.

How do you send a simple 'Hello World!' response in Express?

A res.send('Hello World!')

B console.log('Hello World!')

C app.listen('Hello World!')

D npm install 'Hello World!'

Use res.send('Hello World!') inside a route to send a response.

Describe the steps to install Express and start a basic server.

Think about commands and basic code to get Express running.

Explain why we need to use app.listen() in an Express application.

Consider what happens after writing routes.