An array is a collection of data items stored under a single name. Array provides a mechanism for declaring and accessing several data items with only one identifier, thereby simplifying the task of data management.
we use an array when we have to deal with multiple data items.
There are three types of array.
1. Numeric/Indexed array.
2. Associative array.
3. Multidimensional Array.
When an array index is represented by a number, it is called Numeric/Indexed array. By default, numeric array index starts from 0.
Syntax:- $array_name  = Value;
For Example:- $name= “Sushant”;
$name = “Sushant”;
When an array index is represented by a String, it is called Associative array.
For Example:- $Fee [“Sushant”] = 520;
Arrays of Arrays is known as Multidimensional Array.