array_diff < PHP
The array_diff function returns an array containing all the values from the first array that are not present in any of the other arrays.
$array1 = ["a", "b", "c"];
$array2 = ["c", "d", "e"];
$arrayDiff = array_diff($array1, $array2);
print_r($arrayDiff);
// Array
// (
// [0] => a
// [1] => b
// )