<?php

$arr_one = ['one', 'two', 'three'];
$arr_two = ['four', 'five', 'six'];

print_r(array_merge($arr_one, $arr_two));

/* Array
(
    [0] => one
    [1] => two
    [2] => three
    [3] => four
    [4] => five
    [5] => six
) */