(PHP 5 >= 5.2.0)
Representation of time zone.
DateTimeZone::AFRICA
Africa time zones.
DateTimeZone::AMERICA
America time zones.
DateTimeZone::ANTARCTICA
Antarctica time zones.
DateTimeZone::ARCTIC
Arctic time zones.
DateTimeZone::ASIA
Asia time zones.
DateTimeZone::ATLANTIC
Atlantic time zones.
DateTimeZone::AUSTRALIA
Australia time zones.
DateTimeZone::EUROPE
Europe time zones.
DateTimeZone::INDIAN
Indian time zones.
DateTimeZone::PACIFIC
Pacific time zones.
DateTimeZone::UTC
UTC time zones.
DateTimeZone::ALL
All time zones.
DateTimeZone::ALL_WITH_BC
All time zones including backwards compatible.
DateTimeZone::PER_COUNTRY
Time zones per country.