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Web Worker

A JavaScript script executed from an HTML page that runs in the background, independently of other scripts that may also have been executed from the same HTML page.

Categoryweb

Overview

Web Workers allow for multi-threading in JavaScript. They enable you to run heavy computations in a background thread, preventing the main UI thread from becoming unresponsive or 'janky.'

Key Features

  • Parallelism: Run code simultaneously with the main thread.
  • No DOM Access: Workers cannot directly manipulate the DOM for safety reasons.
  • Message Passing: Communication with the main thread is done via postMessage and onmessage events.
  • Improved Performance: Ideal for data processing, image manipulation, and complex calculations.

Comparison

Unlike Service Workers, Web Workers are tied to the specific page that created them and do not persist after the page is closed.

Related Terms

Service Worker