Amazing content Akshay :-) Have some quick questions: 1) When does the event loop actually start ? Are only asynchronous web api callbacks are registered in web api environment ? Does the web api environment stores only the callback function and pushes the same callback to queue/microtask queue? How does it matter if we delay for setTimeout would be 0ms. Then callback will move to queue without any wait ?

Things learned: 1. Browser has superpowers that are lent to JS engine to execute some tasks, these superpowers include web API's such as console, location, DOM API, setTimeout, fetch, local storage. 2. Callback functions and event handers are first stored in Web API environment and then transferred to callback queue. 3. Promises and mutation observer are stored in API environment and then transferred to microtask queue. 4. Event loop continuously observes call stack and when it is empty it transfers task to call stack. 5. Micro task is given priority over callback tasks. 6. Too many micro tasks generated can cause Starvation (nit giving time to callback tasks to execute).

In JavaScript, the event loop, microtask queue, callback queue, and call stack are all key components that help manage the asynchronous nature of the language. Call Stack: The call stack is a data structure that keeps track of the function calls in your code. It follows the Last In, First Out (LIFO) principle, meaning the last function that gets pushed onto the stack is the first one to be popped off when the function completes. Callback Queue (Task Queue): The callback queue, also known as the task queue, holds tasks (callbacks or events) that are ready to be executed. These tasks usually come from asynchronous operations, such as DOM events, HTTP requests, or timers. Event Loop: The event loop is responsible for continuously checking the call stack and the callback queue. If the call stack is empty, the event loop takes the first task from the callback queue and pushes it onto the call stack for execution. Microtask Queue: The microtask queue holds tasks that are also ready to be executed but has a higher priority than the callback queue. Microtasks are usually scheduled by JavaScript promises, mutation observers, and other similar mechanisms. Here's how they work together: When an asynchronous operation is encountered, such as a setTimeout or a Promise, the callback associated with that operation is sent to the callback queue after the specified time or when the Promise settles. When the call stack is empty (no functions being executed), the event loop takes the first task from the microtask queue and pushes it onto the call stack. If the microtask queue is empty, the event loop looks at the callback queue and pushes the first task onto the call stack. This process repeats, allowing JavaScript to handle asynchronous operations without blocking the main thread. Understanding these concepts is crucial for writing efficient and responsive asynchronous JavaScript code, as it helps you manage the order of execution and prevent blocking the user interface.

This is probably the only course that does not bore me. I feel like going through one more episode even when I'm done for the day. You make concepts very easy to understand. Thank you for this series, Akshay.

After almost two years, here I am again, experiencing the same exhilarating rush of emotions just like the very first time. It's truly amazing to journey through this entire session once more.

Cracked 2 interviews back to back and answered Event Loop quest in such a way that there were no cross question left for interviewers to ask. Thanks again Akshay

Watch `Maha-Episode` of this series: JS ENGINE Architecture 🔥 - kzfaq.info/get/bejne/aL16f5Rq3KqsZmw.html How was this video? Let me know in the comments below, I read each and every comment! ❤️

Great video, Akshay! I appreciate the way you break things down and that you take the time to reiterate even the simpler concepts. You have the heart of a teacher, and we could not be more grateful.

Goodness gracious what a video! Amazing summary of the Event Loop. The knowledge being provided in these videos is a blessing to all honestly.

A good teacher with quality content doesn't needs a marketing and advertisement. Ppl fallback with him naturally. Thanks Akshay for being a good teacher😊

I recently interviewed a candidate for a FEE role and when I asked him about Web APIs, he said, 'It's a browser superpower', I was bloody confused, only now I know.

This is probably the only course which does not bore me. I feel like going through one more episode even when I'm done for the day. You make concepts very easy to understand. Thank you for this series Akshay.

Best series that I have found on KZfaq till today. Thanks! Amazing deep explanation. WOW... WOW... WOW...

Amazing Explanation. Kudos to it. The things you explained in 40 mins... takes lot more to sink in if I had read a book or watched somebody else. Thank you!

I cannot stop watching "Namaste Javascript". As a beginner, I am quickly able to grasp so many new terms and explanations. Hats Off Man!

After watching too many javascript tutorials on youtube , i can guarantee that Akshay bro's course was the best and excellent...........❤❤

I usually don't comment as you pointed out, but this video being so comprehensive and detailed yet so simple to understand made me comment here. The explanation was too good and anyone could easily understand them. I highly recommend going through this series serially as that will help you understand every concept deeply and get your foundations strong. Thank you Akshay for making this series public as this will help new developers (and experienced too) to not just code to finish work on deadline but will also make them fall in love with this beautiful language.

This is the best JS tutorial I've seen on the internet. It is quality than a paid course. Thank you Akshay!!!.

Beautifully explained, I've never dived down as deep into JS as this before.

We should be incredibly thankful for all the efforts he put into completing the entire series with great enthusiasm. I bet there are hardly any tutors on KZfaq who provide free content that motivates beginners to continue their journey. I truly appreciate all your efforts, brother, and I will definitely purchase the React JS course.

This is amazing. I got hooked to this playlist. It is exactly the kind of depth I was looking for in the tutorials. Thanks a lot.

Forget everything, just admire the way he is doing everything so that we can understand everything. The guy isn't backing off for one single moment.

All your videos are amazing and provide infinite clarity on some of the most taken- for- granted foundation concepts of JS Thank you so much for making this available for free!!!

Wow, this is gold. There's no other content about event loop as good as this on the whole KZfaq. This is the simplest and most effective way of teaching what event loop is. Thank you Akshay for the content.

You made it easy to understand what is happening under the covers through the JS Event Loop. Thanks for taking the trouble to break things down for us to understand.

With this understanding of the event loop, I feel like I can nail an interview. Nicely Explained. I always find your videos simple and full of knowledge.

You are super amazing and I can promise after this I will never ever forget what an event loop is.

Wow, mind blowing stuff, discovered your channel so late and have to admire your efforts. This playlist is no short of a gem🔥🔥🔥🔥

Thank you so much for this explanation Akshay, loving the series so far!

Akshay you made so easy to understand. The way of explanation is feels like a story telling. Good job keep the hard work goes on. Cheers 👍👍

The best thing about his videos is you never get bored even if the video is 1hr long. Kudos to you brother!! Keep up the good work!!

nothing is better than this and your explanation and set in my mind for lifetime, cannot thank you enough. you are truly a JS GOD!!!

I had no knowledge about javascript but because of you started learning it and now it feels soo easy. It's been two weeks now, i watch one video from this series everyday.

At the end i felt like i have achieved knowledge of a whole book only on event loop. Really filing like master of event loop. Really thanks to you.

This is awesome never seen this kind of one's expecting more like this deep drive understanding the javascript, I really enjoyed with this video really great sir 🎉🎉

watching your playlist from 4 days just in love with your explanation.

Never thought Event loop would be that simple. Hats off to you!!!

Thanks a lot akhay bhaiya, in a world where most of the students in the first year of college are running behind Competitive programming and ML, it is really a breathe of fresh air when someone as influential as you is teaching Javascript in depth for free.. again thanks a lot!

No one ever taught about this as clear as you do. Thank you so much Akshay.

The quality, concise JS series provided by only you sir !!!!! We are lucky to have you, providing such crystal clear explanations of the JS topics at free of cost; really the most humble, passionate person you are...😇

This video is perfect for anyone learning JavaScript! You explain everything so clearly, and the examples make complex concepts so much easier to understand. Kudos to you for breaking it down in such an engaging and informative way. Great work, and looking forward to more tutorials like this! Thanks

Namaste Javascript! 🙏 These video are like new discovery to me. I love it definitely . Thank you so much for your amazing videos.

This is the first time that i'm commenting on a youtube video. That was a very great explanation. Lots of Love and lots of respect. More Power to you man.

A good teacher with quality content doesn't needs a marketing and advertisement. Ppl fallback with him naturally. Thanks Akshay sir for being a good teacher

This is the best explaination on javascript execution i have seen on youtube. Great efforts bro.

#gajab(virtual hug emoji , searched specially for this video only.) watched in one go at 2Am, initially thought to skip bcz of length. but while watching got excited and completed without any pause. you will get to know about following terminology, callstack global execution context event loop Web APIs (e.g. setTimeout , DOMs , fetch, console) context callback queue(or task queue) microtask queue promises , mutation observer startvation of callback all the things are explained with three examples : setTimeout, dom apis with click event , fetch api + setTimeout. Great video, I can confidently say that this guy has not learned the conecpt in this deep bcz of simply working in company. Its because of his great interest/passion for Javascript. keep empowering us with such a great knowledge. I don't comment or like generally, but on this video have commented & liked both.

After watching a lot of the content in that topic I can say this one was the best IMHO! You have answered all my questions :) Thanks so much!

Thanks man Thank-you so muchhhh. I used to always forget this concept and come here after for the clear concept. Came back after 2 years when I needed to revise this. Thank you again

I am a student .I started learning JavaScript 3 months back .I am very passionate to know how actually JS works behind the scene. For me this NamasteJS series is like dream came true

At first, I clicked on your video to clarify my concepts on hoisting. However, I ended up watching the entire series for multiple times. It is surprising how you can have such a thorough understanding of JavaScript, and such in-depth explanation of all the concepts, both theoretically and practically. Love your passion, thank you so much!

This event video loop is like open the eyes to know the browser has a lot of super powers. It can do anything. Thanks a lot.

I would say just amazing. No could ever explain it in that much simple and deeper way! Loved it ❤

I feel like i have found a hidden treasure, amazing worth much more than the paid content. Thank you so much for such grate knowledge :)

Hi Akshay, This is the most important video and you nailed it in this video, hats off to you man. Thanks for explaining the evnt loop and callback queue with so ease.

आपके समर्पण के लिए धन्यवाद !🔥 Not only did it help me understand how browsers work, but it also made me love JavaScript even more❤‍🔥

Найкраще і найлегше пояснення, дякую!!

Great Efforts and best explanations ,Thanks is just not enough to be thankful for such a great content .

spent whole day studying about event loop and finally understood it in these 40 mins, Best explained.

After learning from your video i have fallen in love with the js how beautifully it is working behind the scene you are simply the master of depth knowledge and the way you deliver it simply amazing because of you i started reading documentation thanks a lot ❣

Mind blown by this video. I've learnt so much from this series. Thank you so much!

This is not only a Js series, It's a masterpiece 💯

You are great man. I love those teachers who really enjoy teaching ❤️ Love and Respect from Bangladesh 🇧🇩

Akshay.....WHOA! I am just now watching all of the Namaste JavaScript videos in order, one by one. I have learned so much this far this weekend; I wish I knew all of this when I started out learning JS a few years ago. Oh the interviews I would have passed! haha. This particular video was all new info to me and you explained it simply and wonderfully. This video was a true BLESSING to my understanding. It's now three years after you initially. made this video so I hope its all still relevant LOL. Thank you once again!!!

Fun Fact: In most of the browsers, there is an event loop for each browser tab this makes every process isolated and avoid a webpage with infinite loops and heavy processing to freeze the entire browser 🚀

The only Dev serie on youtube that worth a comment, like and subscribe its a masterpiece

So much of contents from you sir. its actually mind blowing. I m following your videos since few days. Hats off to your efforts taken

"I found this video to be the most enjoyable till now in the series. Thank you for the excellent explanations that made it easy for me to understand."

This video should be shared by all senior javascript devs to their junior devs ones . Amazing @akshay sir

I am a java developer. Before watching this series I really used to hate JavaScript because it really behaves differently than other programming languages . I have watched a lot of tutorial series of JS but, your content is PURE GOLD! As you said at the start of this series, your GOAL is to make people fall in love with JS. I think you have succeeded. ♥️

This course give me more energy when I started. because the way you teach is loved it. i can't say thankyou I say Dhanyawad namaste javascript

Absolutely fall in love with Namaste JavaScript.Hat's off you...

Amazing video ! Mind blowing content. Now the time has come when the best of the best content is available for free. Education is no more dependent on money. Thanks for the whole series. I am doing my BCA (first year) and learning web dev on my own, this series is helping me a lot, clearing the core fundamentals like how things actually work. Eagerly waiting for "promises" episode !!

The Event Loop pushes the "queue" into the Call Stack only when the Call Stack is empty (i.e. the global execution context has been pushed off the call stack). The order in which the Event Loop works is: 1. Call Stack 2. Microtask Queue 3. Callback Queue Hope this helps :)

Most amazing content on Javascript. This videos was superb about how event loop works. Hats off to you @Akshay Saini Sir! I can bet no one is there on any platform with a sound knowledge and strong core concepts of JS like you have .

Best video ever on js for conceptual clarity. Thank you Akshay hands off bro.

I have never seen anyone teaching concepts with so much depth, clarity and ease. The content is unbeatable, the delivery enthusiastic and love how eager you are to make JS easy for everyone. Thank you for putting all this effort and coming up with this series. Worth every second of watch time.

@Akshay Bro I can't tell how beautiful your lectures are and Seriously understood the concept of event loop thoroughly , Thank you soo much for making it free for all , this series is a gem Bro

Your passion is so contagious !! You are really good explaining this concepts. I wish you all the best.

Hi Akshay, I am following this series from more than a week and it really helps to understand each and every concept which you are covering and before covering this series am unaware of call back function, global execution context, closure but now I have an idea and can explain to my friend about this concept. This video is also an amazing one and got to know about Microtask Queue and Event Loop and WEB API, you are doing a great job and keeps continuing this work because there are so many folks who wanted to learn and if you are continuing this kind of work then not only you but each and every individual will be happy by watching your video which has deep explanation in it.

this type of detailed breakdown is not even in so called 'bootcamps' , your should have atleast 1M subscribers

It's Awesome 🤯. You are Genius🦸‍♂️ guy . Thank you❤️ so much for sharing this deep🧜 and Magical🧚 hidden world of JS.

Best video on the internet explaining Event Loop and Callback Queue❤

I don't think a better explaination exists for this. Thanks a lot!

An awesome explaination. I just wish my college teacher's would have taught their subjects with this much enthusiasm.

Best thing is that He himself requests us to stay for some more time to learn. In clg, even if we request, teachers weren't explaining clearly. Akshay "ದೇವರು ಒಳ್ಳೇದು ಮಾಡಲಿ🙌"

Blown away again. You're an amazing teacher Akshay!

Wow.. Best teacher on KZfaq for real ! your work is amazing dude thank you so much !

This " Namaste javascript " feels like the recursion of pure quality content... Just waiting for your next videos...thanks brother🔥🔥

The tutorial video is very easy to understand as a bigger level dev. We are thankful for your hard work. your effort will help us to make good dev. thanks, buddy we are very glad for Indian dev are also showing interest in creating Valuable contain creation. We are getting very positive vibes when we learn from Indian KZfaqrs. Your presentation and teaching technics and Video and Audio Quality are very good.

loved the video. I always had confusion how callback functions pop up or how event listeners work. This made everything easy. NO DOUBTS REMAINING. It is amazing how many OS concepts like priority queue and task scheduling works in the browser itself.

The explanation was mindblowing. You deserve a standing ovation. Quality content.

I don't usually write comments on KZfaq tutorials, but the content of this guy forced me to do so. More power to you ❤‍🔥❤‍🔥

Loved this Akshay!! I literally had no idea so many things are going on behind the scenes and I've been working on JS for more than a year.

This video just blew my mind !! thank you soo much for explaining these concepts.

I think this is my best decision to watch your videos for js . Every other channel i always see that they directly start from console.log and making projects but they don't teach these deep details that we needed. You have build the confidence within me for my interviews. Amazing ❤

OMG! The more I get deeper into event loop, I am feeling I need to dig deeper. This is mind blowing explanation and details. I liked the neon effects of the sketches you draw while explaining. Thank you so much for putting extreme efforts in making this video and sharing the knowledge. I would like to know now about event loop in node.js and particularly phases of event loop in node.js. :)

Event loop is one the most important concept for every JS interviews.

The explanation was upto the point and more more clear. You have done the amazing job. You have made it very easy for us to understand this topic more clearly.

You have cleared my core concept for the Event loop in one go. Thank you so much for your effort. 💌

First of all I want to say Huge Thank You 🙏🏻. I am a flutter dev. The language used in Flutter is Dart. In one of my interviews the interviewer asked me “How dart program get executed? How dart engine works? What is dart VM? What is JIT and AOT?” Honestly speaking I don’t know any of the above correctly. After the interview I searched for above topics and got some good articles on Medium. One of that articles stated that dart event loops are similar to JavaScript. You know what quickly comes into my mind is the great place to understand this concept is NAMASTE JAVASCRIPT(Event Loop). I really enjoyed every millisecond of 41:45. Thanks again 🙏🏻.