EJS Basics

This lesson covers EJS Basics. Let us learn this step by step — no rush, no jargon first.

What you will learn

• What ejs basics means — in normal words, not textbook words
• How it works step by step
• Code you can run today on your laptop
• Where teams use this in real projects

Before you start

• Software: Node.js LTS from nodejs.org, VS Code, and a terminal
• Knowledge: Earlier lessons in this Node.js course
• Previous lesson: Error Handling — Complete Guide

Explain it simply

EJS embeds JavaScript inside HTML templates. Express can render a page and pass data to it.

Why developers use this

• Core skill for web backends
• Huge community and docs
• Leads to REST and auth

How it works (step by step)

1. A browser or app sends an HTTP request to your server.
2. Express middleware runs in order (log, parse JSON, check auth).
3. The route handler for EJS Basics runs your logic.
4. You send JSON or HTML back with the right status code (200, 201, 404, 500).

Code example — type this yourself

app.set('view engine', 'ejs');
app.get('/', (req, res) => {
  res.render('home', { title: 'Dashboard', user: 'Sandeep' });
});

home.ejs lives in a views folder. Use <%= title %> to print escaped values.

What each part does

• app.set('view engine', 'ejs'); — Line 1: runs as written.
• app.get('/', (req, res) => { — Defines what happens when a client hits this URL and HTTP method.
• res.render('home', { title: 'Dashboard', user: 'Sandeep' }); — Line 3: runs as written.
• }); — Line 4: runs as written.

Real life: where EJS Basics shows up

A college admin panel uses EJS Basics with Express: students hit /courses, teachers hit /grades, and shared middleware checks login once for every page.

Try it yourself — hands-on

1. Create a new file (e.g. ejs-basics-demo.js) in an empty folder
2. Type the example code for EJS Basics yourself — typing helps memory
3. Run node on that file and read the output
4. Change one line (a value, a message, a route path) and run again to see what breaks or improves

Common mistakes (avoid these)

• Skipping the terminal — EJS Basics only feels easy after you run code yourself.

Interview note

Be ready to explain EJS Basics with a real trade-off: what problem it solves and what you would not use it for.

Summary

• You can explain EJS Basics in your own words
• You ran working code — not just read about it
• You know one mistake to avoid and one real place teams use this