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WHAT IS DST?
WHO INVENTED IT?
WHY IT IS OBSERVED?
WHERE IT IS OBSERVED
HISTORY OF DST
PROS AND CONS OF DST
Just as sunflowers
turn their heads to
catch every sunbeam,
so too have we
discovered a simple
way to get more from
our sun. We've
learned to save energy
and enjoy sunny
summer evenings by
switching our clocks
an hour forward in
the summer.




Daylight Saving Time ,often referred to as
"Summer Time―, is a way of making better use
of the daylight in the evenings by setting the
clocks forward one hour during the longer
days of summer, and back again in the fall.
Daylight saving time (DST) is a change in the
standard time with the purpose of getting
better use of the daylight by having the sun
rise one hour later in the morning and set
one hour later in the evening.
The idea of daylight
saving was first
conceived by
Benjamin
Franklin during
his sojourn as an
American delegate
in Paris in 1784, in
an essay, "An
Economical
Project”.










The invention of DST was mainly credited to William Willett in
1905 when he came up with the idea of moving the clocks
forward in the summer to take advantage of the daylight in the
mornings and the lighter evenings.
His proposal suggested moving the clocks 20 minutes forward
each of four Sundays in April, and switching them back by the
same amount on four Sundays in September.
Willett’s daylight saving plan caught the attention of Robert
Pearce who introduced a bill to the House of Commons in
February 1908.
The first Daylight Saving Bill was drafted in 1909 and presented
to Parliament several times but the bill was opposed by
many, especially farmers and thus the bill was never made into a
law.
Willett died in 1915 without getting the chance to see his idea
come to life.









DST was first adopted to replace artificial lighting so they could
save fuel for the war effort in Germany during World War I at
11:00pm (23:00) on April 30, 1916.
It was quickly followed by Britain and many countries from both
sides, including the United States.
Many countries reverted back to standard time post-World War
I, and it wasn’t until the next World War that DST would make its
return to many countries in order to save vital energy resources for
the war.
President Franklin D. Roosevelt instituted year-round DST in the
United States, called ―War Time‖ during World War II from February
9, 1942 to September 30, 1945. The law was enforced 40 days
after the bombing of Pearl Harbor and during this time, time zones
were called ―Eastern War Time‖, ―Central War Time‖, and ―Pacific War
Time‖. After the surrender of Japan in mid-August 1945, the time
zones were relabeled ―Peace Time‖.
Daylight saving was first recognized as an energy saving aspect
during World War II when Double Summer Time was applied in
Britain which moved the clocks two hours ahead of GMT during the
summer and one hour ahead of GMT during the winter.






Daylight saving time (DST) has been a subject of recurring debate in the
United States, the United Kingdom, and many other countries around the
world for about a hundred years. Ancient civilizations were known to
practice a similar process of the concept of DST where they would adjust
their daily schedules in accordance to the sun, such as the Roman water
clocks that used different scales for different months of the year.
The idea of daylight saving time was first conceived by Benjamin Franklin
in 1784 during his stay in Paris. He published an essay titled ―An
Economical Project for Diminishing the Cost of Light‖ that proposed to
economize the use of candles by rising earlier to make use of the
morning sunlight.
Although many believe that Benjamin Franklin invented DST, some say
that modern DST was first proposed in 1895 by George Vernon
Hudson, an entomologist from New Zealand. Hudson presented a paper
to the Wellington Philosophical Society that proposed a two-hour shift
forward in October and a two-hour shift back in March. He followed up
his proposal with an article in 1898, and although there was interest in
the idea, it was never followed through.










DST caused widespread confusion from 1945 to 1966 for trains, buses and the
broadcasting industry in the US because many states and localities were free to
choose when and if they would observe DST.
Congress decided to end the confusion and establish the Uniform Time Act of
1966 that stated DST would begin on the last Sunday of April and end on the
last Sunday of October. However, states still had the ability to be exempt from
DST by passing a local ordinance.
The US Congress extended DST to a period of ten months in 1974 and eight
months in 1975, in hopes to save energy following the 1973 oil embargo.
The trial period showed that DST saved the equivalent in energy of 10,000
barrels of oil each day, but DST still proved to be controversial.
Many complained that the dark winter mornings endangered the lives of
children going to school.
After the energy crisis was over in 1976, the US changed their DST schedule
again to begin on the last Sunday in April.
DST was amended again to begin on the first Sunday in April in 1987. Further
changes were made after the introduction of the Energy Policy Act of 2005.
Northern Hemisphere
 Many countries in the northern hemisphere observe
DST, but not all. Daylight saving time begins in the
northern hemisphere between March–April and ends
between September–November. Standard time begins
in the northern hemisphere between September–
November and ends between March–April.
Southern Hemisphere
 Daylight saving time begins in the southern
hemisphere between September–November and ends
between March–April. Standard time begins in the
southern hemisphere between March–April and ends
between September–November. Many countries in the
southern hemisphere may observe DST.






Many countries observe DST, and many do not. Many countries use DST
to make better use of the daylight in the evenings. Many people believe
that DST could be linked to fewer road accidents and injuries. The extra
hour of daylight in the evening is said to give children more social time
and can boost the tourism industry because it increases the amount of
outdoor activities.
DST is also used to save energy and reduce artificial light needed during
the evening hours — clocks are set one hour ahead during the spring,
and one hour back to standard time in the autumn. However, many
studies disagree about DST's energy savings and while some studies
show a positive outcome, others do not.
It is difficult to predict what will happen with Daylight Saving Time in the
future. The daylight saving date in many countries may change from
time to time due to special events or conditions.The United States,
Canada and some other countries extended DST in 2007. The new start
date is the second Sunday in March (previously the first Sunday in April)
through to the first Sunday in November (previously the last Sunday in
October).









Today it is almost always one hour ahead, but throughout history
there have been several variants on this, such as half adjustment
(30 minutes) or double adjustment (two hours), and adjustments
of 20 and 40 minutes have also been used.
A two-hour adjustment was used in several countries during the
1940s and elsewhere at times.
A half adjustment was sometimes used in New Zealand in the
first half of the 20th century.
Australia's Lord Howe Island (UTC+10:30) follows a DST
schedule in which clocks are moved 30 minutes forward to
UTC+11, which is Australian Eastern Daylight Time (AEDT) when
it is on DST.
Sometimes DST is used for a longer period than just the
summer, as it was in the United States during World War II.
From February 3, 1942 to September 30, 1945 most of the
United States had DST all year; it was called ―War Time.‖











Many people around the world treasure the extra hour of daylight in the
afternoon because they work later hours, exercise in the evenings or need to
complete outdoor household chores such as mowing the grass, gardening or
fixing windows, roofs or other parts.
Others have reported that daylight saving time could be linked to reduced
road injuries. A joint Transport Research Laboratory and University College of
London study predicted that less people would be killed and injured in road
accidents if one hour of daylight was transferred from the morning to the
afternoon.
Some people believe that the extra hour of daylight in the afternoon or evening
gives children more time to interact with a parent who works or studies during
the day.
It gives families time to socialize or enjoy an outdoor meal together.
Others say that the increased daylight leisure time gives them a chance to
participate in recreational activities, such as swimming, boating, surfing, or
tennis, after a long day of work or study.
There are arguments on the idea that daylight saving time reduces electricity
usage and promotes energy efficiency.




The extended daylight saving time in some parts
of Australia and New Zealand has affected mobile
phones, computers, and other electronic
devices, including major integrated
telecommunication company Telstra’s speaking
clock. Many clocks needed to be adjusted
manually or via software updates from device
makers.
Mixed flight schedules and inaccurate
transportation timetables have caused confusion
among travelers, for both personal and business
purposes, and regular commuters. The transport
industry needed to take into account the costs
for adjusting to new time schedules.
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New microsoft office power point presentation

  • 1.
  • 2.       WHAT IS DST? WHO INVENTED IT? WHY IT IS OBSERVED? WHERE IT IS OBSERVED HISTORY OF DST PROS AND CONS OF DST
  • 3. Just as sunflowers turn their heads to catch every sunbeam, so too have we discovered a simple way to get more from our sun. We've learned to save energy and enjoy sunny summer evenings by switching our clocks an hour forward in the summer.
  • 4.   Daylight Saving Time ,often referred to as "Summer Time―, is a way of making better use of the daylight in the evenings by setting the clocks forward one hour during the longer days of summer, and back again in the fall. Daylight saving time (DST) is a change in the standard time with the purpose of getting better use of the daylight by having the sun rise one hour later in the morning and set one hour later in the evening.
  • 5. The idea of daylight saving was first conceived by Benjamin Franklin during his sojourn as an American delegate in Paris in 1784, in an essay, "An Economical Project”.
  • 6.      The invention of DST was mainly credited to William Willett in 1905 when he came up with the idea of moving the clocks forward in the summer to take advantage of the daylight in the mornings and the lighter evenings. His proposal suggested moving the clocks 20 minutes forward each of four Sundays in April, and switching them back by the same amount on four Sundays in September. Willett’s daylight saving plan caught the attention of Robert Pearce who introduced a bill to the House of Commons in February 1908. The first Daylight Saving Bill was drafted in 1909 and presented to Parliament several times but the bill was opposed by many, especially farmers and thus the bill was never made into a law. Willett died in 1915 without getting the chance to see his idea come to life.
  • 7.      DST was first adopted to replace artificial lighting so they could save fuel for the war effort in Germany during World War I at 11:00pm (23:00) on April 30, 1916. It was quickly followed by Britain and many countries from both sides, including the United States. Many countries reverted back to standard time post-World War I, and it wasn’t until the next World War that DST would make its return to many countries in order to save vital energy resources for the war. President Franklin D. Roosevelt instituted year-round DST in the United States, called ―War Time‖ during World War II from February 9, 1942 to September 30, 1945. The law was enforced 40 days after the bombing of Pearl Harbor and during this time, time zones were called ―Eastern War Time‖, ―Central War Time‖, and ―Pacific War Time‖. After the surrender of Japan in mid-August 1945, the time zones were relabeled ―Peace Time‖. Daylight saving was first recognized as an energy saving aspect during World War II when Double Summer Time was applied in Britain which moved the clocks two hours ahead of GMT during the summer and one hour ahead of GMT during the winter.
  • 8.    Daylight saving time (DST) has been a subject of recurring debate in the United States, the United Kingdom, and many other countries around the world for about a hundred years. Ancient civilizations were known to practice a similar process of the concept of DST where they would adjust their daily schedules in accordance to the sun, such as the Roman water clocks that used different scales for different months of the year. The idea of daylight saving time was first conceived by Benjamin Franklin in 1784 during his stay in Paris. He published an essay titled ―An Economical Project for Diminishing the Cost of Light‖ that proposed to economize the use of candles by rising earlier to make use of the morning sunlight. Although many believe that Benjamin Franklin invented DST, some say that modern DST was first proposed in 1895 by George Vernon Hudson, an entomologist from New Zealand. Hudson presented a paper to the Wellington Philosophical Society that proposed a two-hour shift forward in October and a two-hour shift back in March. He followed up his proposal with an article in 1898, and although there was interest in the idea, it was never followed through.
  • 9.        DST caused widespread confusion from 1945 to 1966 for trains, buses and the broadcasting industry in the US because many states and localities were free to choose when and if they would observe DST. Congress decided to end the confusion and establish the Uniform Time Act of 1966 that stated DST would begin on the last Sunday of April and end on the last Sunday of October. However, states still had the ability to be exempt from DST by passing a local ordinance. The US Congress extended DST to a period of ten months in 1974 and eight months in 1975, in hopes to save energy following the 1973 oil embargo. The trial period showed that DST saved the equivalent in energy of 10,000 barrels of oil each day, but DST still proved to be controversial. Many complained that the dark winter mornings endangered the lives of children going to school. After the energy crisis was over in 1976, the US changed their DST schedule again to begin on the last Sunday in April. DST was amended again to begin on the first Sunday in April in 1987. Further changes were made after the introduction of the Energy Policy Act of 2005.
  • 10. Northern Hemisphere  Many countries in the northern hemisphere observe DST, but not all. Daylight saving time begins in the northern hemisphere between March–April and ends between September–November. Standard time begins in the northern hemisphere between September– November and ends between March–April. Southern Hemisphere  Daylight saving time begins in the southern hemisphere between September–November and ends between March–April. Standard time begins in the southern hemisphere between March–April and ends between September–November. Many countries in the southern hemisphere may observe DST.
  • 11.    Many countries observe DST, and many do not. Many countries use DST to make better use of the daylight in the evenings. Many people believe that DST could be linked to fewer road accidents and injuries. The extra hour of daylight in the evening is said to give children more social time and can boost the tourism industry because it increases the amount of outdoor activities. DST is also used to save energy and reduce artificial light needed during the evening hours — clocks are set one hour ahead during the spring, and one hour back to standard time in the autumn. However, many studies disagree about DST's energy savings and while some studies show a positive outcome, others do not. It is difficult to predict what will happen with Daylight Saving Time in the future. The daylight saving date in many countries may change from time to time due to special events or conditions.The United States, Canada and some other countries extended DST in 2007. The new start date is the second Sunday in March (previously the first Sunday in April) through to the first Sunday in November (previously the last Sunday in October).
  • 12.       Today it is almost always one hour ahead, but throughout history there have been several variants on this, such as half adjustment (30 minutes) or double adjustment (two hours), and adjustments of 20 and 40 minutes have also been used. A two-hour adjustment was used in several countries during the 1940s and elsewhere at times. A half adjustment was sometimes used in New Zealand in the first half of the 20th century. Australia's Lord Howe Island (UTC+10:30) follows a DST schedule in which clocks are moved 30 minutes forward to UTC+11, which is Australian Eastern Daylight Time (AEDT) when it is on DST. Sometimes DST is used for a longer period than just the summer, as it was in the United States during World War II. From February 3, 1942 to September 30, 1945 most of the United States had DST all year; it was called ―War Time.‖
  • 13.
  • 14.       Many people around the world treasure the extra hour of daylight in the afternoon because they work later hours, exercise in the evenings or need to complete outdoor household chores such as mowing the grass, gardening or fixing windows, roofs or other parts. Others have reported that daylight saving time could be linked to reduced road injuries. A joint Transport Research Laboratory and University College of London study predicted that less people would be killed and injured in road accidents if one hour of daylight was transferred from the morning to the afternoon. Some people believe that the extra hour of daylight in the afternoon or evening gives children more time to interact with a parent who works or studies during the day. It gives families time to socialize or enjoy an outdoor meal together. Others say that the increased daylight leisure time gives them a chance to participate in recreational activities, such as swimming, boating, surfing, or tennis, after a long day of work or study. There are arguments on the idea that daylight saving time reduces electricity usage and promotes energy efficiency.
  • 15.   The extended daylight saving time in some parts of Australia and New Zealand has affected mobile phones, computers, and other electronic devices, including major integrated telecommunication company Telstra’s speaking clock. Many clocks needed to be adjusted manually or via software updates from device makers. Mixed flight schedules and inaccurate transportation timetables have caused confusion among travelers, for both personal and business purposes, and regular commuters. The transport industry needed to take into account the costs for adjusting to new time schedules.