The Eventloop in JavaScript - How does it work?

on YouTube ↗41m

" summary

Explains that the event loop actually orchestrates when callbacks run, showing microtask queue vs macro task queue, how Promises, setTimeout and fetch are scheduled, and why a busy loop freezes the UI. Demonstrates a small demo page (fast/slow buttons) and a VS Code Typescript Worksheet plugin running Node/Chrome runtimes; both work and reveal ordering surprises (zero ms setTimeout still defers; first 40 quiz entrants, 28 got one question right). Live-coding verifies behaviors.

AI-written summary · about

" chapters (9)

1. 0:00Introduction
2. 1:49Engine vs runtime
3. 5:19Why event loop needed
4. 7:50Call stack and queues
5. 12:26Web APIs and event loop
6. 16:41Event loop mechanics
7. 17:04Live coding demo
8. 27:09Interactive quiz
9. 40:14Q&A and closing

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