WEBVTT

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Welcome to this video.

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Today we're going to dive into the basics
of next generation JavaScript syntax.

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var is an outdated syntax
for creating a new variable.

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From now on, we'll be using let instead.

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So let's change up our variables to let

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here. Let creates a variables, but its
scoping behavior is different from var.

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If we want to create variable
that never changes, we use const keyword.

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Const creates a constant

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which makes it clear in the code that the
value of that variable will never change.

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For example,
if we are planning on assigning a new

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value to age, then we can
let it be a let variable.

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But if we never change our name,
then we can make it constant.

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If we try to set name to something else

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and run the code,
we're going to get an error because we're

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trying to assign a value
to a constant variable.

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So let's try to reassign the name here

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and let's say that I wanted to
have a value of my full name.

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If I try to run this code,

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we're getting an error saying:
assignment to constant variable.

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The idea behind const is to use it as
often as possible to make it clear

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in the code what's happening

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if something should never change

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make it a const so that you get
an error if you accidentally change it.

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Thanks for watching and see
you in the next video.