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43. Web Workers & Off-Main-Thread Execution

Background computation without UI blocking.

1 min read3 questionsup to 50 XPtopic 43/50

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Web Workers execute JavaScript in background threads. They do not have access to the DOM and communicate with the main thread via message passing.

js
const worker = new Worker("worker.js");
worker.postMessage({ data });
worker.onmessage = (e) => console.log(e.data);

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Check your understanding

  1. 1. Can a Web Worker directly access the DOM document or window?

  2. 2. How is data communicated between main thread and workers?

  3. 3. What task is ideal for a Web Worker?

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