Var vs Const vs Let (ES6) - Beau teaches JavaScript

Learn about the difference between const, var, and let in JavaScript ES6 (ECMAScript 6).
Code
🔗 codepen.io/beaucarnes/pen/MbMN...
Other resources on topic:
🔗 www.jstips.co/en/keyword-var-v...
🔗 • var, let and const - W...
Beau Carnes on Twitter: / carnesbeau
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[@ylioo]

This is how you explain it, idk what's up with this 20 min vidoes, let vs var vs const

[@kotoriitsuka1097]

Sometimes it seems like ppl do philosophy...

[@MCTVARG]

Yeah, we are missing scope a little bit in depth here, what happens when its inside a function as CONST? and as Var? inside an if statement? etc...

[@Joshua8224]

check mmtuts video on this. The best!

[@_runic]

jesus christ, no kidding. it was hell trying to find this beautiful explanation, i literally only needed to hear the first minute of it to understand.

[@abhinavkumar8396]

Best exact ,to the point,explanation. Beautiful.

[@PratikRatnaparkhi]

go beau! go beau! I love this guy!

[@pratikpokharel5490]

crisp and clear,covered everything needed less than 4mins.THANKS

[@rayjaymor8754]

In less than 4 minutes you explained to me in an easily understandable manner what 30 minute videos and several pages of documentation couldn't get through my skull. Thank you!

[@robertcruz2080]

same here bro.

[@aceborja1656]

Thank you once again Beau for clarifying.

[@mikestuff2114]

Thank you for keeping it short and to the point.

[@pleabargain]

Many thanks! Much clearer now!

[@itzDJ73]

Very helpful. Thank you!

[@_runic]

tl;dr
let - local variables that can be changed
var - global variables that can be changed
const - constant variables that cannot be changed

[@TealDaubs]

Fucking thank you. Scoured the internet for this answer.

[@_runic]

@@TealDaubs lol never thought this would help anyone

[@martiananomaly]

*tl;dw

[@_runic]

@@martiananomaly no, *tl;dr. look it up

[@christianrodier3381]

That helped a great deal thanks.

[@theonewhodoesPoland]

Clear explanations, thanks for sharing!

[@SamiNami]

Thanks

[@ashfepranto8621]

Thanks a lot dude..

[@ashilshah3376]

On point thankyou :)

[@truptisutar2975]

good explanation

[@batfan1939]

Does this mean we don't need to change or "increment" _i_ anymore? We can use _let_ in loops, and have all of them be _i = foo,_ _i < bar,_ _i++?_

[@antsanders0893]

Thank you for making this 80 times easier than Codeacademy lol

[@anthonyraja5601]

Thank you!!!!!!!!!!!!!!!!!!!!!

[@stevenshelby2675]

This guy makes you think you're watching this video at 1.5x speed

[@sua4443]

should you use let instead of var when you can or does it not really matter?

[@biagio_montelisciani]

thanks bro

[@Mikael97]

Everything is clear to me now. Thanks for explaining the difference between const, let and var.

[@mirataoskoi5855]

Guys what do you think I should do : keep learning JS or start working as a content manager for a company?

[@yanivsalman9685]

you can push to a const variable thats important (:

[@moza260]

ok the var and const is easy thing to remember when first learn, so the let key point is scoop right?

[@hyunchae2431]

without explanation on hoisting, it is not clear why 'var' variable is already available even before it is defined.

[@rodwinpieterse1950]

It actually is. The JS engine 'hoists' a variable assigned with the var keyword out of the flow before it starts executing synchronously.

[@p33yush]

var also binds itself to window object, but let and const dont do that

[@khaouladjouabi7270]

what is the name of this complier ?

[@sayantaniguha8519]

for(var i=1;i

[@ashok2484]

Bro ...what are the basic things are known in js

[@trappedcat3615]

I just use var, closures, and caps to indicate constants. I'll use const and let in 5 years once I don't need to depend on a compiler to interpret them.

[@BeauCarnes]

Some people think you should never use var. I wouldn't go that far, though. 😃 medium.com/javascript-scene/javascript-es6-var-let-or-const-ba58b8dcde75#.sn9gfcmp6

[@trappedcat3615]

Beau Carnes I'm looking forward to never using var

[@zlackbiro]

If we used code for hack, is that counting as for good, hack++ :D

[@shrdn2960]

Based.

[@aybak3k]

let: block-lvl VARs - values can be changed
const: values never change
var: srsly u don need an explaination for dis:)

[@sandiladhikari7903]

And if you use for(i = 0; i < 3; i++) without assigning neither let nor var keyword, the i becomes global variable.

[@debjyotichattopadhyay6679]

watched at 0.5* speed

[@meru_lpz]

i can feel you, 0.75 here

[@oufcena5092]

slow CPU? "Human Processing Unit" LOL

[@unperrier5998]

did you know that semicolons are optional? Why bother then?

[@antoniocastellanos3830]

I’m new but it’s because sometimes they are required so it’s a good habbit to just use them even if they arnt

[@chexitout]

Also most other C based languages do require them, so it's a good habit to get into if you ever end up moving to other languages 👍

[@unperrier5998]

@@chexitout I disagree.
We should do our best to use the language syntax and idioms.

[@boriiinglastname8810]

Ur voice is weird

[@sua4443]

should you use let instead of var when you can or does it not really matter?