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[MUSIC]

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Hey what's up, my name is Dustin, and
I'm a developer here at Treehouse.

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Today, I wanna take you through using the
JavaScript array method known as includes.

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As the name suggests, this method checks
if an array includes a specific value and

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returns true or false respectively.

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Let's hop into some code and
see how this works.

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Make sure to check out the description or
teacher's notes down below for

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related resources.

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If you're ready, let's get into it.

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First, let's check out the official
MDN documentation for this method.

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It's pretty straightforward.

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According to MDN, the includes method
determines whether an array includes

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a certain value among its entries,
returning true or false as appropriate.

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Sounds pretty simple.

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Let's practice it a bit.

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I'll open up my text editor
with an empty app.js file, and

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I'll run this file with Node.

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If you're unfamiliar with Node or
don't have it installed,

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you can run this code in your
browser's developer console.

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Let's set up a brand new array, I'll call
this names and we'll throw in some names.

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Let's write jamie, kandra, and taylor.

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Underneath our array,
let's write a console.log method, and

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inside of that we can write our names
array and chain on our includes method.

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Inside of our includes method,
let's write the string bob.

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If I hit save and open up our terminal and
write node app.js,

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you'll see we get back false.

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And this is because bob does
not appear in our array.

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Let's change bob with kandra.

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I'll hit save and
run node app.js in my terminal again, and

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this time we get back true.

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This is because kandra
appears in our array.

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This method is really straightforward but
can also do some complex things.

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I'll link below a video where I
use the includes method to create

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a dynamic search feature for a web app.

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And that about covers it for
the includes JavaScript array method.

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I hope this guide helped and
I'll see you in the next one.

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Until then, have fun and happy coding.