PHP Arrays

## Arrays
An array is a special variable and data structure that stores more than one value in a single variable.

## Types of Arrays

1. Indexed arrays
1. Associative arrays
1. Multidimensional arrays

For more information about PHP arrays, click [here.](https://www.w3schools.com/php/php_arrays.asp)

@blessnathan01

Review the repository's existing PHP materials to determine where this PHP Arrays content belongs and whether the issue requests adding or revising it. The issue provides no target file, test, or explicit change; completion should be defined before work begins, such as an agreed placement and finalized arrays section.

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