Daylight saving time (DST), also known as daylight savings time or daylight time (United States, Canada, and Australia), and summer time (United Kingdom, European Union, and some other countries),
the practice of advancing clocks (typically by one hour) 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 ("spring forward") and set clocks back by one hour in autumn ("fall back") to return to standard time.
The idea of aligning waking hours to daylight hours to conserve candles was first proposed in 1784 by American polymath Benjamin Franklin.
In a satirical letter to the editor of
The Journal of Paris,
Franklin suggested that waking up earlier in the summer would economize candle usage and calculated considerable savings.
In 1895, New Zealand entomologist and astronomer George Hudson proposed the idea of changing clocks by two hours every spring to the Wellington Philosophical Society,
as he wanted to have more daylight hours to devote to collecting and examining insects.
In 1907, British resident William Willett presented the idea as a way to save energy. After some serious consideration, it was not implemented.