I wonder what this output of echo json_encode(new \DateTime()); means:
{
"date":"2019-04-16 14:43:15.126710",
"timezone_type":3,
"timezone":"Europe\/Berlin"
}
date and timezone are obvious... but what is this timezone_type? The official documentation didn't help me much. The page about DateTime speaks of no such thing, it just mentions you can get/set a DateTimeZone. The page about DateTimeZone doesn't help either.
So... what is it? Where does PHP get it from? And what is it good for?