Choosing the best data structures and algorithms for a particular task is one of the keys to developing high-performance software. A data structure is a collection of data organized in some fashion. The structure not only
stores data but also supports operations for accessing and manipulating the data.

In object-oriented thinking, a data structure, also known as a container or container object, is an object that stores other objects, referred to as data or elements. To define a data structure is essentially to define a class. The class for a data structure should use data fields to store data and provide methods to support such operations as search, insertion, and deletion. To create a data structure is therefore to create an instance from the class. You can then apply the methods on the instance to manipulate the data structure, such as inserting an element into or deleting an element from the data structure.

This Section introduced the ArrayList class, which is a data structure to store elements in a list. Java provides several more data structures that can be used to organize and manipulate data efficiently. These are commonly known as Java Collections Framework.