Node.js: What is the difference between cluster and worker_threads in Node.js?

1const cluster = require("cluster");
2const http = require("http");
3
4if (cluster.isMaster) {
5    // Master process
6    for (let i = 0; i < 4; i++) {
7        cluster.fork();
8    }
9} else {
10    // Worker process
11    http.createServer((req, res) => {
12        res.end("Hello");
13    }).listen(3000);
14}

1const { Worker, isMainThread, parentPort } = require("worker_threads");
2
3if (isMainThread) {
4    const worker = new Worker(__filename);
5    worker.on("message", (msg) => console.log(msg));
6} else {
7    parentPort.postMessage("Hello from worker");
8}