What is the EventEmitter class?

Short answer: How do you create and use custom events? EventEmitter allows objects to emit named events and listen for them. Example: const EventEmitter = require('events'); const emitter = new EventEmitter(); emitter.on('greet', (name) => { console.log(`Hello, ${name}!`); }); emitter.emit('greet', 'Alice'); Output: Hello, Alice! It’s fundamental for asynchronous communication in Node.js.

Example code

How do you create and use custom events? EventEmitter allows objects to emit named events and listen for them. Example: const EventEmitter = require('events');
const emitter = new EventEmitter(); emitter.on('greet', (name) => { console.log(`Hello, ${name}!`); }); emitter.emit('greet', 'Alice'); Output: Hello, Alice! It’s fundamental for asynchronous communication in Node.js.

Real-world example (ShopNest)

A ShopNest BFF in Node.js aggregates catalog and price APIs for the React storefront.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.