Posted Date: 11/06/2017

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What Is Daylight Saving Time?

DST is a seasonal time change measure where clocks are set ahead of standard time during part of the year, usually by 1 hour. As DST starts, the Sun rises and sets later, on the clock, than the day before.

Today, about 40% of countries worldwide use it to make better use of daylight and to conserve energy.

Who Invented DST?

If you think Daylight Saving Time is a good idea, thank New Zealand scientist George Vernon Hudson and British builder William Willett. In 1895, Hudson presented a paper to the Wellington Philosophical Society, proposing a 2-hour shift forward in October and a 2-hour shift back in March. There was interest in the idea, but it was never followed through.

In 1905, independently from Hudson, British builder William Willett suggested setting the clocks ahead 20 minutes on each of the 4 Sundays in April, and switching them back by the same amount on each of the 4 Sundays in September, a total of 8 time switches per year

Benjamin Frankin, the Father of DST?

Many sources also credit Benjamin Franklin with being the first to suggest seasonal time change. However, the idea voiced by the American inventor and politician in 1784 can hardly be described as fundamental for the development of modern DST. After all, it did not even involve turning the clocks. In a letter to the editor of the Journal of Paris, which was entitled “An Economical Project for Diminishing the Cost of Light”, Franklin simply suggested that Parisians could economize candle usage by getting people out of bed earlier in the morning. What's more: Franklin meant it as a joke.

Daylight Saving Today

Daylight Saving Time is now used in over 70 countries worldwide and affects over 1 billion people every year. The beginning and end dates vary from one country to another.