Oct 5, 2020 · Event loop. The JavaScript event loop takes the first call in the callback queue and adds it to the call stack as soon as it's empty.

The Event Loop has one simple job - to monitor the Call Stack, the Callback Queue and Micro task queue. If the Call Stack is empty, the Event Loop will take the first event from the micro task queue then from the callback queue and will push it to the Call Stack, which effectively runs it.

May 3, 2020 · ♻️ Event Loop What happens when you have function calls that take a large amount of time to execute in the Call Stack? For example. Executing a for loop from 1 to 10B; Making a network request; Doing image processing; Let's take an example.

Aug 14, 2024 · The event loop is responsible for managing the execution of tasks in JavaScript. It continuously checks the call stack and the task queue to determine what to execute next.

Aug 10, 2019 · The JavaScript Event Loop Explained with Examples The event loop is a core concept in JavaScript that enables non-blocking, asynchronous behavior. Understanding how the event loop...

Feb 18, 2025 · JavaScript’s asynchronous prowess lies in its elegant orchestration of the call stack, Web APIs, and the event loop—a system that enables non-blocking execution despite its single-threaded nature.

The Event Loop continuously checks if the call stack is empty, and if that's the case, checks for the first available task in the Task Queue, and moves this to the Call Stack for execution. Another popular callback-based Web API is setTimeout .

Jun 18, 2024 · The Event Loop checks whether the Call Stack is empty and, if so, pushes callbacks from the queue to the call stack. Example: setTimeout(() => console.log('Hello'), 0) will be executed after the synchronous code finishes, despite the 0ms timeout.

May 1, 2025 · To avoid blocking, JavaScript (along with the environment it runs in — like browsers or Node.js) uses a set of tools: Web APIs, callback/task queues, and the event loop. This trio helps JS handle things like network requests, timers, or …

Dec 25, 2020 · Web APIs, the callback queue, and the event loop are all features that the browser provides. A representation of NodeJS would look similar, but in this article, I’ll focus on how JavaScript works in the browser.