the equivalent is an associative array.
usage:
$a = array( "key1" => "value1", "key2" => "value2");
$a["key3"] = "value3";
echo $a["key"];
you can use as many dimensions as you want:
$b = array("a" => "aa", "b" => "bb");
$c = array("first" => $a, "second" => $b);
echo $c["second"]["a"]; // wil print aa
