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I know we've mentioned array's quite a few times within the previous lessons, and we finally got to

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them and we are saving the best till last because arrays are really, really cool.

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I'm going to show you what they are and how you can use them.

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So just like objects, they give us the ability of a single variable and assign a bunch of values to

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it so that we can reference those values just with a single variable.

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So in this case, we've got shopping, but all of the contents of shopping, we have access to all that

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full list and then we can update change it as needed.

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We can also contain objects within arrays, arrays within arrays, so it can get fairly complex.

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We can use all the different data types as we've seen before, where we're using strings, we're using

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booleans numbers, null, undefined.

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So all of them are valid and they can all sit within the array in order to get valid values from the

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arrays.

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So they are zero based index values.

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So unlike what we saw with objects, arrays are limited to using the index value in order to retrieve

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back whatever value index value is associated with it.

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So we've got an example here where we're using the list we're referencing.

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We're trying to pull back item number three in the list, and that's where we're pulling back.

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So remember, it's starting at zero.

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So number three would be 35.

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And you can see that zero is Lowrance.

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One speaks to is true, three is 35.

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So using the array name and the index value, that's how we can retrieve values that are contained within

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that array.

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So the challenge for this lesson is to create an array with different types of data and then return

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the values of those different data types.

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So get the value into the console of the below array.

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We've got the default array called the list and there's a combination of that.

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There's an object in there.

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There's another array in there, there's a number.

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So there's all these different values that are contained in there.

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So the objective just to try it out and get 55 out, get to out, see how many times it takes you in

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order to retrieve back that information.

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And as you can see, two is a little bit tricky there.

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So this is going to be a little bit more of a challenge to put in the console.

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You can pause the video and I'll show you the solution coming up.

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And as well, this is a quick sneak peek at the solution will list out the list.

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And you can see that all of that information is contained.

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So what we want it to do is retrieve back some of the values that are contained in here.

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And in particular, we were looking to retrieve back 35 and number two there and also retrieve back

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55.

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So we want to get 55 and two.

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So those are two of the more complex ones, because the first one is contained within the object and

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the second one is contained within the array.

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So let's try it out within the console.

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And as you can see, when you are using the list, you can get the values back from the list.

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So using the index value so you can retrieve back the first first one.

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So zero based.

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Remember that.

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And then the second one is one.

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And you can go all the way through the entire list until you get to the one that you want to see.

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So if we were to list number six, this is where we retrieve back that object.

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So we've got a choice here where to retrieve back the score 55.

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We can use the list just as we set it, but we want to get score back.

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So we've got two choices because we've got an option to do it as a dot notation or a bracket notation.

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And as you can see, they're going to return back.

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So either one of these is correct.

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And let's type this into the console.

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So either one of these was a correct way to retrieve it back.

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And then the other object or another value that we want to retrieve back is coming from the list.

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And this one is going to be contained in number seven.

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And as you can see, this is an array that's contained within the array.

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So in order to retrieve back, the format is the same.

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So if we want to retrieve the second item, we do one.

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So retrieving it is the same way.

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And sometimes it does get fairly complex because you have to really dig through these and you'll see

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instances of arrays that contain objects and then objects that contain arrays again so they can get

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fairly complex.

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So it is important to practice and try it out and just make sure that you are able to retrieve back

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any one of the values contained within the list.