An array stores multiple values in one single variable. Arrays are essential when working with lists of data, such as a list of users, products, or settings.
Indexed arrays use numeric indexes (starting at 0) to store and access values.
<?php
$cars = array("Volvo", "BMW", "Toyota");
echo "I like " . $cars[0] . ", " . $cars[1] . " and " . $cars[2] . ".";
?>
Associative arrays are arrays that use named keys that you assign to them. These are very similar to dictionaries or hash maps in other languages.
<?php
$age = array("Peter"=>"35", "Ben"=>"37", "Joe"=>"43");
echo "Peter is " . $age['Peter'] . " years old.";
?>
A multidimensional array is an array containing one or more arrays. PHP supports deep multidimensional arrays, which are frequently used to store complex datasets from databases.
(Note: You can get the length of an array using the count() function).