Spring forward... Daylight Saving Time.

2 a.m. on the Second Sunday in March

It's ingrained in our consciousness almost as much as the A-B-Cs or our spelling reminder of "i before e...." And it's a regular event, though perhaps a bit less regular than the swallows coming back to Capistrano.

Beginning in 2007, Daylight Saving Time is extended one month and begins for most of the United States at: 2 a.m. on the Second Sunday in March and lasts until 2 a.m. on the First Sunday of November.

Daylight saving time (DST; also summer time in British English) is the convention of advancing clocks so that afternoons have more daylight and mornings have less. Typically clocks are adjusted forward one hour near the start of spring and are adjusted backward in autumn. Modern DST was first proposed in 1907 by William Willett. Many countries have used it since then; details vary by location and change occasionally.

The practice is controversial.[1] Adding daylight to afternoons benefits retailing, sports, and other activities that exploit sunlight after working hours,[2] but causes problems for farming, entertainment and other occupations tied to the sun.[3][4] Extra afternoon daylight reduces traffic fatalities;[5] its effect on health and crime is less clear. An early goal of DST was to reduce evening usage of incandescent lighting, formerly a primary use of electricity;[6] modern heating and cooling usage patterns can cause DST to increase electricity consumption.[7]

DST's clock shifts can serve as fire safety reminders,[8] but they complicate timekeeping and can disrupt meetings, travel, billing, record keeping, medical devices, and heavy equipment.[9] Many computer-based systems can adjust their clocks automatically, but this can be limited and error-prone, particularly when DST rules change.[10]

Contents
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* 1 Origin
* 2 Benefits and drawbacks
o 2.1 Energy use
o 2.2 Economic effects
o 2.3 Public safety
o 2.4 Health
o 2.5 Complexity
* 3 Politics
* 4 Observance practices
* 5 Terminology
* 6 Computing
o 6.1 Zoneinfo
o 6.2 Microsoft Windows
* 7 References
* 8 Further reading
* 9 External links

http://en.wikipedia.org/wiki/Daylight_saving_time