What are worker threads in Node.js, and when would you use them?

Worker threads allow you to run JavaScript operations in parallel, providing a way to execute CPU-intensive tasks without blocking the main thread. They are useful for tasks that require heavy computation, such as image processing or data analysis. Example of creating a worker thread:

const { Worker } = require('worker_threads');

const worker = new Worker('./worker.js');

worker.on('message', message => {
  console.log(`Received from worker: ${message}`);
});

worker.postMessage('Start working');