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What the heck is the event loop anyway? | Philip Roberts | JSConf EU

JSConf · 3.8M views · 2014-10-09 · 26:53

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Overview

Philip Roberts explains the JavaScript event loop, call stack, callbacks and asynchronous behavior with live visualizations using a tool he built. It demystifies terms like non-blocking and single-threaded.

On Hacker News

HN commenters repeatedly name it as the best explanation of the JS event loop and the first thing to watch before tackling async code.

Recommended by 16 HN people across 14 months · HN mentions 2015–2025

Topics

Web developmentPython, Ruby & scripting languages
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event loopasync javascriptcall stackcallbacksvisualization

What people said

krisgenre · 2020-11 · Strong recommendation

This one is my all time favorite - What the heck is the event loop anyway? | Philip Roberts | JSConf EU [VIDEO]

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_bxg1 · 2020-02 · Strong recommendation

I got to know the nuances of the language by working with it for years and having to figure out why various things didn't work at different points, but it doesn't sound like that's your style. This isn't comprehensive, but it's probably the most helpful deep-dive I've ever seen about some aspect of JavaScript. It's about the Event Loop, which is one of the biggest differences between JS and comparable languages like Python: [VIDEO] Contrary to what you might think, even though the event loop is in some sense "distinct from the language", it isn't simply an API. You can't really have JavaScript without the event loop; it exists in both the browser and in Node, and is the basis for most of the language's advantages.

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keyvin · 2018-10 · Strong recommendation

Another event loop talk from Philip Roberts. The tool he created to display the event loop in real time is fantastic. [VIDEO]

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Sources

Video by JSConf, played through YouTube.

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