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Welcome back to Learn to Code and JavaScript and this lecture, when I start looking at a raise for

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next four lectures, I'm going to look at arrays, including this one.

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The first two are going to be pretty basic.

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The next two are going to be a little bit more advanced.

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So it's possible you may want to skip the second two until later.

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So anyway, let's get into arrays.

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What always give us they're a collection of values and the values do not have to be the same type in

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JavaScript.

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So think of what we know so far, which is variables.

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So it's kind of boring to say that I have a name.

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I can't do much with it.

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What I might want to do is have 100 names and do something with all 100 of them.

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So this is what arrays allow you to do.

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So you have a very literals Nerdfighteria square brackets with the values separated by commas so it

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could look like this Mirae equals square bracket one comma three.

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Come a five, come on seven, come in line in the square brackets, semicolon.

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Or it could look like this.

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You don't have to be the same types.

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Another day equals five comma.

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Hello cometrue.

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So this area has three different types.

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Array elements are then accessed by zero based index.

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So in our example with my array, my array index one or people say sub one, the value is three because

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the zero value is number one.

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The number one value is number three.

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And this is a lot like strings of recall string characters are zero based.

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You can update a value in an array so I can say my array index or my razib two equals fifty five.

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So this replaces the five with 55 and then an array length property like string length can give you

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the number of elements in the array.

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So the actual array length can't be changed once it's initialized.

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But there are certain methods that return an array with a different length.

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So we'll take a look at those.

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So let's look at some examples of initializing a raise and making use of the values in an array.

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So here's our starting application, so let's do a few things with the race so array variables are defined

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like other variables you use left or const.

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So I can say let my array equals to come before a comma six, comma eight.

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And now this array will have five elements with those values.

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So if I just cancel, log out an array

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and the length.

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Here's what we get.

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So I can see that already tells me the length in parentheses, so the council tells me that and if I

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open up a little a little triangle, it will expand the element.

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So if there is a thousand elements that will show them to me on the first one.

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And then my life is out here and you see the life is built into the ray.

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So it's listed in there as well.

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So let's make a change.

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Two equals five thousand.

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And we will just copy this.

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And run it, so now our number five has been replaced by 5000 in the array.

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I can reassign a new array to the array so I can say my array equals Hello World.

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Twenty three.

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And then when we come to work that out, we'll have the Nuray, so keep in mind, this is a totally

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distinct array.

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Then the array that we created up here only has three elements.

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It's got two strings, one number.

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A world 23.

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All right, so that's an introduction to initializing an array and manipulating it.

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So next, we're going to look at some selected array methods.