# Web Worker

A browser worker that runs JavaScript away from the page's main thread.

## What is **Web Worker** in JavaScript?

**Web Worker** — A browser worker that runs JavaScript away from the page's main thread.

```javascript
const worker = new Worker("worker.js");
worker.postMessage({ task: "resize" });
```

Level: Freelancer · [More JavaScript terms at this level](https://www.ask-codey.com/glossary/subjects/javascript/freelancer)

Updated: September 27, 2026

Source: https://www.ask-codey.com/glossary/web-worker