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# Data Structures Introduction

**Data structures** are basically just collections of values with relationships among them and functions/methods that can be applied to the data. Arrays and objects are built-in data structures.

For example, arrays store data in a sorted order. They also come with built-in methods like `filter` or `reverse` that are inherited from the `Array` prototype.

In the same vein, we will be creating custom data structures by defining our own **classes**. Instances of these classes will organize the data in specific ways and will inherit methods and properties that allow us to manipulate the data.