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There's one last method that we're going to be covering in JavaScript, and that's the map method,

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and it kind of ties everything together where we can reconstruct a brand new array using contents from

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existing data so we can create a brand new array by calling a function and looping through each one

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of the elements.

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So, of course, there is a challenge for this lesson, and this is to use maps.

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So this map is going to work similar to what we've seen earlier where we can reconstruct the array.

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So we've got an array num array, all numbers in there.

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And we're going to use that existing array and rebuild it.

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Multiplying each one of the values by 50 and then returning it back into my party and I would lock out

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the values of my operate into the console.

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So go ahead and try this out.

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You can pause the video and I'll walk you through it coming up.

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So first thing that we need to do is construct our array.

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So this is just going to be a no arrests are going to have a bunch of numbers in here.

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Just come a separate them and they can just be any number we want.

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Or we could use the existing array that we have within the sample.

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So once we've created our array, save that and you can double check just to make sure you've got your

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array there.

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And we're going to build a brand new array.

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So we're taking our map and we're going to use the number array.

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So that existing array that we have and using the map method, we've got function for X at first of

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all, console log out the value of X so you can see it within the console.

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It's going to run the block a code.

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So what it's doing is it's going through each one of the items in the array and holding the value of

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that item as X. So we can do something with it.

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And just as we saw before, whatever we're returning back is going to be part of the new map array.

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So we're constructing this brand new map array and we're checking to see we're taking X and we're multiplying

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it by 50.

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So now when we get our brand new constructed array, all of the values we've used, all of the values

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in the current number array, and we've simply multiplied them by 50.

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So this is a really useful function as you've got a lot of data within an array.

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And if you want to do something with that data, you can use a map in order to run blocks of code and

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then reconstruct brand new arrays from that data.