See also:

• Kids and Teens: School Time: Science: Astronomy and Space: Time  (25)
• Science: Astronomy: Amateur: Sky Calendars  (15)
• Science: Astronomy: Calendars and Timekeeping  (54)
• Science: Earth Sciences: Geology: Geochronology  (13)
• Science: Physics: Relativity: Time Travel  (16)
• Society: History: Timelines  (63)
• Society: Philosophy: Philosophy of Science: Physics: Time and Timelessness  (13)

A Brief History of Time  www.perseus.tufts.edu/GreekScience/Students/Chris/TIME2.html Early origins and historical perspectives of time measurement.

The Calendar  www.skeptics.com.au/journal/calendar.htm Summarizes the history of various calendars developed and used over the centuries.

Calendar Studies  www.hermetic.ch/cal_stud.htm Information about calendar history and calendar reform.

Calendar Zone  www.calendarzone.com A categorized collection of calendar related sites.

English Calendar  www.albion.edu/english/calendar Includes an ecclesiastical calendar and a section on old and new style dating.

A Few Facts Concerning GMT, UT, and the RGO  www.apparent-wind.com/gmt-explained.html Explains the differences between several time systems.

A History of Time  www-history.mcs.st-andrews.ac.uk/HistTopics/Time_1.html Explains the importance of concept of time in the history of mathematics, science and measurement.

Infoplease: Daylight Saving Time  www.infoplease.com/spot/daylight1.html Information and history about Daylight Saving Time all over the world.

International Standard Date and Time Notation  www.cl.cam.ac.uk/~mgk25/iso-time.html An overview of the ISO 8601 notation for dates.

Internet Encyclopedia of Philosophy: Time  www.iep.utm.edu/t/time.htm Time has been studied for thousands of years. Nevertheless, many issues remain to be resolved. This article explores both what is now known about time and what is controversial and unresolved.

NIST Time and Frequency Division  tf.nist.gov The National Institute of Standards and Technology maintains time and frequency standards for the United States.

NPR : 'Seize the Daylight': A History of Clock Chaos  www.npr.org/templates/story/story.php?storyId=4572036 Benjamin Franklin first called for the government to tinker with clock hours in the 1780s. But it wasn't until World War I that the United States adopted daylight-saving time as a way to get more efficiency out of the day. "Seize the Daylight" Author David Prerau talks about the complicated politics and curious history of DST, and he shares an excerpt from his book. [4:54 streaming audio broadcast]

This Day In History  www.history.com/this-day-in-history.do Today in history every day - often with pictures and sound.

Time  scienceworld.wolfram.com/astronomy/Time.html Provides descriptions of several standards of time.

Time FAQ  www.faqs.org/faqs/astronomy/faq/part3 Frequently Asked Questions about time (from sci.astro news group)

Time Zone and Daylight Saving Time Data  www.twinsun.com/tz/tz-link.htm A directory of sites providing descriptions of civil timekeeping concepts, source code, databases, and maps.

Today's Calendar and Clock Page  www.ecben.net/calendar.shtml Information on all things relating to calendars, dates, holidays, and time. Find today's date on several different cultural and religious calendars. Includes section on Celestial data, countdown clocks, and information on the dates past events.

United States Code  tycho.usno.navy.mil/260.html Weights, measures and standard time.

U.S. Time Zones  aa.usno.navy.mil/faq/docs/us_tzones History of standard time in the U.S.

A Walk Through Time  physics.nist.gov/GenInt/Time/time.html Evolution of timekeeping through the centuries.

Wikipedia: Time  en.wikipedia.org/wiki/Time Time is a common term for the experience of duration, and a fundamental quantity of measuring systems. Article explains time definitions, history of measurements, perceptions in religion, philosophy and science.

Z-Time  www.maybeck.com/ztime Article on the time at 0 degrees longitude. Covers the timezone origin, GMT, UTC, GCT, ZULU and JIG.