What are common pitfalls when passing arrays in PHP between different files?

Common pitfalls when passing arrays in PHP between different files include not properly including the file that contains the array, not using the correct variable scope, and not serializing the array before passing it. To solve this, make sure to include the file where the array is defined using `include` or `require`, use `global` keyword to access the array in different files, and serialize the array before passing it to ensure data integrity.

// File containing the array
$array = [1, 2, 3];

// Serialize the array before passing it
$serialized_array = serialize($array);

// In another file
include 'file_containing_array.php';

// Unserialize the array to access its values
$array = unserialize($serialized_array);