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In this lecture, we are going to take a look at arrays.

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Storing a list of data is a common type of action you may want to perform.

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For example, we can store lists of posts, users purchases, et cetera.

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Arrays are commonly used in languages to store a list of data.

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Rust supports arrays But there's one caveat the size of an array is fixed.

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For example, if the size of an array is five, the array may never contain more than five values.

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We can't add new items to the array.

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Rust constraints the size of an array after initialization.

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Let's give arrays a try at the bottom of our function.

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Let's create a variable called items.

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An array can be created by adding new pair of square brackets, the square brackets may contain our

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collection of values.

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Each value is separated by a comma.

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For this demonstration, let's add five numbers.

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The size of the array is five.

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We can hover our mouse to verify the size.

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Our editor has annotated the array.

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This feature is another thing to be aware of.

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The values in the array must be of the same type.

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In our example, the types are integers after the type, the size of the array is written.

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We have the option of annotating the array after the variable name.

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Let's add an annotation arrays can be annotated by adding a pair of square brackets.

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The annotation is going to need two pieces of information.

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The first piece of information is the data type of the array.

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For this example, we are creating an array of integers.

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Next, we need to add a semicolon, followed by the size of the array.

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This step is optional, but you may need to know how to annotate an array if they comply, and there

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are Canton for the array.

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Let's try logging the way by using the print line.

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Macro arrays can't be printed.

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We need to use a placeholder inside the string and a debug placeholder.

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For the second to arguments will pass in the array.

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Lastly, let's try running B cargo run command.

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The array gets neatly formatted in the console.

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There's not much else to say about arrays.

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An array must have a fixed size, and the values in an array must have the same type in the next lecture.

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We will begin looking at another data type for storing a collection of data.