Interview Question

What is Web Worker?

A Web Worker runs script separately and communicates through messages.

💡 Concept ✅ Quick Revision ⚡ JavaScript

Answer

A dedicated worker runs a script in a background worker global scope. • It does not directly access the document DOM. • The page and worker communicate by posting messages. • Workers help move suitable computation away from the user-interface event loop.

Example

Code
const worker = new Worker('worker.js');
worker.postMessage({ task: 'calculate' });
worker.onmessage = event => console.log(event.data);

Quick Revision

A Web Worker runs script separately and communicates through messages.