JavaScript Under The Hood [1] - Thread & Call Stack

In this video, we will talk about JavaScript's main thread as well as how the call stack works.
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Timestamps:
1:02 - Thread Of Execution
2:50 - Call Stack Explanation
3:38 - Slide Example 1
4:34 - Slide Example 2
5:16 - Browser Example 1
7:10 - Browser Example 2

[@nudecode]

As always amazing content. Simple step by step easy to under stand, no wank about how much you know, which is often irrelevant to what is being taught. Love that it’s about the “behind the scenes” workings. Confident this will be a great series.

[@mznunaya]

My gawd I love you. You're just amazing. There isn't a single video of yours I haven't watched. Your way of teaching is flawless.

[@horic007]

This series is very useful for people who want an indepth knowledge of Js. Thanks Brad. 🙌🏼

[@ahmad-murery]

Very nice Brad, this will add a new flavor to the channel, the cool thing in callstack tab is that you can click on any stack item to go back and forth in execution time and see how your variables changes and where the error came from in case of any

[@abdouazizndiaye7229]

I thought this the most important concept in JavaScript this video come at the right time cause that’s what I’m actually learning thanks Brad ❤️

[@732brudder]

Thank for this. Timing is perfect. I was recently sort of forced into learning this stuff backwards. I had to learn a bit of React, Vue, and Svelte in order to accomplish something I needed for work. While learning these frameworks I was super unfamiliar with Javascript. I had learned it a bit in college, but never any real world experience. These videos are helping a ton actually understand how JavaScript works under the hood. I learned a lot of this for other languages in college, but have been asking this question a ton. Especially in web development, it's really difficult to understand exactly when certain code will/is being executed. Extremely important lesson to learn if you want to know exactly what you are doing. Thanks for this series, keep this going! Edit: Also loving this insight into the dev tools in web browsers. Also a very skimped over part of my journey to web app development. Will need to clean up some code I've hacked together for some projects.

[@universecode1101]

This lesson is very important. Learn the basics html css and js. Thanks Brad

[@hachikoi-san3901]

This is beyond basic tho

[@Chris-zt4ol]

@@hachikoi-san3901 I think he means fundamentals

[@christopheanfry2425]

Awesome serie idea. I think very important to understand deeper how js works. Very interesting and well explained as usual. 💪🏻

[@lorenainfanter.3099]

Great series! I struggled a little bit with those concepts but you helped me to clarify all. Thank you very much!!

[@nickstaresinic9933]

Very nice, clear explanation of an important (and sometimes confusing) topic -- and in ~9 minutes, too.

[@yousoumar]

Really interesting series. It's really interesting to know what's happening under the hood. Thanks Brad.

[@JigJason93]

Very well explained, I already love this series, thank you for your contribution.

[@LewisChapman-ic1lb]

3:15

[@parvati27]

Brad is the best teacher in the world, thank you brad 💜

[@hamzahmd_]

Thanks, Brad for this high-level stuff.

[@mahdisalmanizadegan5595]

Thank you brad for this amazing series, i wish you all the best possible. more positive energy.

[@bojanchurlinov1385]

Great job Brad, keep up the great work you are doing 😁

[@diegotayro1555]

Maybe the best video topic of this channel and youtube regarding coding.

[@Adnankhan-bl3mc]

Now this series is gold

[@kaloianangelkov4919]

I've been waiting for those kind of videos from a long while! Thanks

[@PoojaSharma-yn5dp]

This channel content is unmatched.👌

[@DanielSmith-yx6zm]

Great Stuff. Definitely the kind of things I want to learn as a developer.

[@tonmoyroy2350]

Awesome tutorial. Thanks Brad ❤️

[@robscherer]

Pumped for this series!

[@Vendavalez]

You’re doing the good work Brad! Thanks!

[@codyfingerson743]

This is awesome! Thanks Brad! Do you by chance have a crash course on DS & Algorithms? I love your style of teaching, and would love to watch a crash course on that!

[@JJ-qy4gf]

I had no idea the source tab is where you can see the call stack! Great video!

[@iloveher9527]

Awesome ❤️ this kind of videos is really important; keep it up 🔥

[@dror-krief]

I love you brad thank you I started follow you because my teacher told me that you are a great source to learn good tech

[@datumcoder]

Thank you for the video Brad! It really helps! 😎

[@dalyryl]

Thanks for this Traversy, this was a very important course despite of rapid changing of JS Libraries and frameworks

[@sojuthomas7727]

Thanks Brad.Loved it ❤️

[@jmonterojr]

This is great stuff. Thanks Brad!

[@dimitrisvain]

Great series! Thank you!

[@BijanProgrammer]

Awesome! I really have high hopes for this series.

[@stu3131]

Outstanding! More deep dives!

[@Marjolein_1979]

This is a very clear explanation.

[@yodkwtf]

you're awesome. Tons of free valuable content

[@muhammadidrees6650]

loving it Brad.

[@rfryanfavour4369]

Thank you Mr Brad, you are the best

[@ismoiljonabduqahhorov5825]

Thanks Brad you are the best ❤️

[@dinaesmaeili1814]

It was awesome mate! thanks for such nice course.

[@seanpalmer1145]

Great stuff as ever. Much appreciated

[@taofeeqomotolani2311]

This is such a great video, I came to watch it after I saw Brad's tweet about a comment he read on probably this video.

[@odehadejoh9966]

Well explained Brad.

[@richardkirigaya8254]

Thank you so much for this brad

[@seemsas]

thank you for the series

[@willadams6217]

Great explanation and example.

[@masroorali9307]

Amazing Brad!

[@yannisstaali3257]

I love this kind of video !!!! Thank you !!

[@georgemoraitis1923]

Amazing information! Thank you very much.

[@AnthonyCandaele]

Very good explanation of the call stack. If your updated Javascript course will be as good as this, I'm looking out for it.

[@programer9620]

Thanks it was really helpful.

[@charbelboughazale3994]

thank you man, you helped me ALOT

[@tamlq97]

Thanks sir, this video was the one I am looking for :3

[@amingrateful7661]

You're just amazing man 👍🏻

[@rubanruban5617]

Nice Video brad, Thank you

[@andrestorres3239]

Great!!!

[@devanshshah1]

i learn more from you then mm college and u have prob helped me get a job

[@RavenOfLaughter]

Well explained

[@josephwong2832]

Brad Traversy is awesome!

[@MartinMasevski]

So much interesting! Thanks

[@moustafamahmoud4948]

Great job sir

[@hrudayd4217]

Waiting for this content from traversymedia, final got

[@mouridamine3237]

i like this series it's good for interview question

[@deejaydev]

Thats whats up, thanks for your deditcation and time.

[@shishirislam8948]

This best time to learn your video..

[@vinaypatil8009]

Awesome sir Please make video on javascript Explain everything about javascript

[@javascriptes]

Awesome stuff

[@vijayakumarv2633]

Good job👍, looking for other videos

[@andrewayad]

Do you know that I immediately hit that like button as soon as I it appears on your new videos even before the video starts playing?

[@Sarvesh_Coder]

Very important 👏 and nice

[@youssefyoutube4536]

Can you believe i came here from chat gpt 😅 Respect man chatgpt recommended your channel !!!

[@jhmesseroux]

amazing 👌

[@mahdikamran8061]

Thank you.

[@JagdishAdusumalli]

This is Gold

[@myestery]

Waiting for this all my career

[@alefsdev]

Thank you!!!!

[@lifeisbeautifu1]

Thank you

[@dimitmoto1716]

Thanks a lot!!!

[@scottlittleton5653]

Hey Brad could you possibly cover "web workers" or "worker threads" as a possible way that JS may be used in a multi-threaded way. I have seen it mentioned before but it would be nice to understand better. thanks for the videos

[@javadmh7827]

Awesome 👌

[@_Iokanaan_Marusidze_]

Thanks

[@subratachatterjee6333]

Sir, You are awesome and the best to me. I want a full stack web development course from you on udemy platform. As of now I have purchased maximum of your courses on udemy. No question arises about the quality and depth of your courses. I have been eagerly waiting to get a complete full stack web development course from you, Sir.

[@azengakevin9599]

Amazing

[@kunnudev7250]

Brother great job please continue awesome videos salute to you plz make videos on c c++ Java oops

[@justlife7]

Best 👍

[@tonyantony1977]

amazing

[@codedancingwithmilos]

Yes Boss!!!

[@nkhan6898]

8:55 Oh Yess!

[@serychristianrenaud]

thank

[@jamesmay5088]

I am first! Thanks for this super content👍👏

[@mpb0406]

Great video. Any plans to get into data structures and algorithms in this new series?

[@Arabian_Epileptic]

I have videos on my channel on that topic

[@wusaby-ush]

That’s great

[@techaddictdude]

Hi where can I get the presentation slides, great video brad.

[@skylench]

It's funny how Brad has to apologize for not being great at certain things when in reality those things couldn't be any better or more comprehensive... Imagine how perfect those things he feels he's good at would actually look. The guy is just a genius

[@awuk3468]

My first WTF moment with JS was the async await, if it is synchronous and single threaded why require the await command, I am still not 100% sure but I am presuming that as the only thing I can think of that requires it is the fetch command that it yields to the rest of the execution whilst running in a kind of background worker? Good video, looking forward to more in the series.

[@CapeSkill]

The await is more so for promise chaining, ''promise to execute y only when x is back with the result''. Fetch or any other async operations are also provided by web api's and they're handled by event loop in callback queue.

[@awuk3468]

@@CapeSkill Ah, ok, makes sense, thanks.

[@abdukhamidtolipov6461]

good

[@acrosstundras]

Great videos. But when you say 'everything is executed line by line' is sounds like there is no compilation step, that the instructions for the machine are interpreted straight from the source code. But there is in fact a compilation step before execution. This detail helps explain some things like hoisting.

[@pulatoff7]

Stackoverflow came out of this😁

[@PabloGnesutta]

Si, could se say that the second example is somewhat more expensive than the first? Because there is more context loaded on the stack at any given time. Or it doesnt work like that?