https://wen.yunshangtool.cn/tags/javascript/Recent content in JavaScript on Dev ToolkitHugo -- gohugo.ioen-usFri, 12 Jun 2026 00:00:00 +0000https://wen.yunshangtool.cn/posts/javascript-event-loop/Fri, 12 Jun 2026 00:00:00 +0000https://wen.yunshangtool.cn/posts/javascript-event-loop/The JavaScript event loop is the backbone of asynchronous programming in JS. Understanding how microtasks and macrotasks work is essential for writing performant code. What is the Event Loop? The event loop continuously checks the call stack and the task queue. When the call stack is empty, it takes the first task from the queue and pushes it onto the stack. Microtasks vs Macrotasks: Promise.then() callbacks go to the microtask queue, while setTimeout callbacks go to the macrotask queue.