<?php $a = array( 'a' => 'apple', 'b' => 'bear', 'c' => 'coffee', ); $b = array( 'a' => 'ant', 'b' => 'bug', 'd' => 'deep', ); echo "\$a + \$b\n"; $c = $a + $b; print_r($c); echo "array_merge(\$a, \$b)\n"; $c = array_merge($a, $b); print_r($c); echo "\$b + \$a\n"; $c = $b + $a; print_r($c); echo "array_merge(\$b, \$a)\n"; $c = array_merge($b, $a); print_r($c);