- An array stores data in memory for later use through a fixed number of cells and a corresponding numeric index for selecting data.
- A queue is a sequential structure that processes elements in the order in which they are entered, often referred to as FIFO (First In, First Out.)
- Linked lists index data rather than positioning elements, using a reference system with elements stored in nodes linked by pointers.
- Trees are a hierarchical structure with “roots” that branch off the top into other, related "child nodes" below.
Several pre-existing data structures exist to solve coding problems with efficiency, thereby reducing the number of programming hours needed to resolve an issue with a systematic method of storing and retrieving data. However, data structures exist to handle specific functions, which means the rest of the code that surrounds the data structure must be written properly in order for the data stored within to be accessible.