A time zone is an area which observes a uniform standard time for legal, commercial and social purposes. Time zones tend to follow the boundaries between countries and their subdivisions instead of strictly following longitude, because it is convenient for areas in frequent communication to keep the same time.
Daylight saving time (DST), also referred to as daylight savings time or simply daylight time, and summer time, is the practice of advancing clocks during warmer months so that darkness falls at a later clock time. The typical implementation of DST is to set clocks forward by one hour in the spring, and to set clocks back by one hour in autumn to return to standard time. As a result, there is one 23-hour day in late winter or early spring and one 25-hour day in autumn.
Japan Standard Time, or Japan Central Standard Time, is the standard time zone in Japan, 9 hours ahead of UTC. Japan does not observe daylight saving time, though its introduction has been debated on several occasions. During World War II, the time zone was often referred to as Tokyo Standard Time.
Summer time in Europe is the variation of standard clock time that is applied in most European countries in the period between spring and autumn, during which clocks are advanced by one hour from the time observed in the rest of the year, with a view to making the most efficient use of seasonal daylight. It corresponds to the notion and practice of daylight saving time (DST) to be found in many other parts of the world.
Time in New Zealand is divided by law into two standard time zones. The main islands use New Zealand Standard Time (NZST), 12 hours in advance of Coordinated Universal Time (UTC) / military M (Mike), while the outlying Chatham Islands use Chatham Standard Time (CHAST), 12 hours 45 minutes in advance of UTC / military M^ (Mike-Three).
Australia uses three main time zones: Australian Western Standard Time, Australian Central Standard Time, and Australian Eastern Standard Time. Time is regulated by the individual state governments, some of which observe daylight saving time (DST). Australia's external territories observe different time zones.
There are eleven time zones in Russia, which currently observe times ranging from UTC+02:00 to UTC+12:00. Daylight saving time (DST) has not been used in Russia since 26 October 2014. From 27 March 2011 to 26 October 2014, permanent DST was used.
Time in Brazil is calculated using standard time, and the country is divided into four standard time zones: UTC−02:00, UTC−03:00, UTC−04:00 and UTC−05:00.
Time in Chile is divided into three time zones. Most of Continental Chile uses the time offset UTC−04:00 in winter time and UTC−03:00 in summer time, while the Magallanes and Chilean Antarctica region uses the time offset UTC-03:00 the whole year. Additionally, Easter Island uses the time offset UTC−06:00 in winter time and UTC−05:00 in summer time.
Bangladesh Standard Time (BST) is the time zone of Bangladesh. It is offset six hours ahead of Coordinated Universal Time, and observed as a national standard throughout the country. Bangladesh briefly observed daylight saving time (DST) in 2009 to cope with the ongoing electricity crisis, but in 2010 the decision was cancelled by the government of Bangladesh.
Samoa uses UTC+13:00 as standard time. It observed daylight saving time from 2010 to 2021, which it observed during summer in the Southern Hemisphere. In 2011, daylight saving time ended on Saturday, 2 April 2011, 04:00 local daylight time and started on Saturday, 24 September 2011, 03:00 local standard time. Because it is located near the equator, Samoa traditionally did not observe daylight saving time. The introduction of daylight saving time was initially planned for 2009 but was postponed for one year in the aftermath of the 2009 Samoa tsunami.
Pakistan has experimented with Daylight Saving Time (DST) a number of times since 2002, shifting local time from UTC+05:00 to UTC+06:00 during various summer periods.
Since 2004, Uruguay had usually observed daylight saving time. Starting in 2006, DST begins on the first Sunday in October and ends on the second Sunday in March of every year. Time zone changed from Standard Time Zone UTC−03:00 to UTC−02:00.
Daylight saving time in the Americas is the arrangement in the Americas by which clocks are advanced by one hour in spring and moved back in autumn, to make the most of seasonal daylight. The practice is widespread in North America, with most of Canada, Mexico, and the United States participating, but much less so in South America.
Daylight saving time is not used in Egypt, however it has been used several times in the past, most recently in 2014.
As of 2018, daylight saving time (DST) is permanently observed in Morocco. Previously, time was advanced to UTC+01:00 at 02:00 on the last Sunday of March, and reverted to UTC±00:00, defined as Greenwich Mean Time locally, at 03:00 on the last Sunday of October. This practice was continued through October 2018, after which clocks were permanently advanced. An exception was made during the month of Ramadan during which clocks reverted to UTC+00:00.
As of 2017, daylight saving time is used in the following Asian countries:
The only African country and regions that use daylight saving time are:
Daylight saving time (DST), also known as summer time, is the practice of advancing clocks during part of the year, typically by one hour around spring and summer, so that daylight ends at a later time of the day. As of 2022, DST is observed in most of Europe, most of North America and parts of Asia around the Northern Hemisphere summer, and in parts of South America and Oceania around the Southern Hemisphere summer. It was also formerly observed in other areas.
Africa, the world's second-largest and second-most populous continent, spans across six different time zone offsets from Coordinated Universal Time (UTC): UTC−01:00 to UTC+04:00. As Africa straddles the equator and tropics, there is little change in daylight hours throughout the year and as such daylight saving time is currently observed in only one country, Morocco, however it was also previously observed in several other countries.
