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Welcome back in the next couple of videos, we are going to look at collections and collections are

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simply a group of the same type of data or different type of data.

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So in Scotland, there are two categories of collections classes that can only hold one type of element

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of a particular data type and then classes that can hold both one type of element or a different type

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of element of.

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So each day that type in Scotland has a clause for holding its element into array is specifically for

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holding integers.

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Boolean array is used for holding true or false values, is used for holding double types than with

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byte array for holding byte values.

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And accordingly, then long and short range, while float array is specifically for holding float.

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So now you must be asking What about a string, for example?

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Well, there we have the array of which is a class that can hold all previously mentioned types, including

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strings and custom types or even classes, and can even hold different types together.

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So there are other classes like list or list of.

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Then we have set or set off.

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And finally, we have map and map of where a key is connected to a value.

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So these are our classes are not mutable, which means you can only read the values but cannot write

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to it.

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List is similar to an array of but with more helper methods for performing operations on its values,

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and the size can be easily increased when needed.

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So it is a class that ensures there are no duplicate values in a group, and map is arranged as a key

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value pair where each value has a key.

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You can use to identify it.

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So here, for example, the key one could be associated to Sun Key two for Monday and so forth.

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There are special classes for both reading and writing, and to a list set and map collections.

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This way, you can easily separate elements that need to be publicly modifiable from those that need

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to be private.

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All right, so now let's write some code and see how to use all of those different lists and collection

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types.