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[MUSIC]

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Hello world, Andrew here, lifelong learner
and JavaScript teacher here at Treehouse.

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For most of JavaScript's life,
there's been only one way to create or

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declare a variable, using the var keyword.

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Most JavaScript programmers
learned this method and

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a lot still use the var keyword, but

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some of the behaviors from using var
can be problematic or unexpected.

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That's why developers of
the JavaScript programming language

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decided to introduce new ways for
creating variables.

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The sixth version of
JavaScript called ES 2015 or

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ECMAScript 2015,
introduce two new keywords.

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Const and let.

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In this workshop,
I'll show you how const and let work.

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And explain why you'll want to use them
instead of var, when declaring variables.

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But first,

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I just want to mention that const and
let work in a similar way to var.

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In each case, you use the keyword var,
const, or let.

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Followed by the name of the variable,
an equal sign and

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the value you want to
put into that variable.

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So, when should you use const and
when should you use let?

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Great questions.

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I'll answer them in the next few videos.