» A History of Time    A two-part article that discusses physicist's evolving view of time.    http://www-history.mcs.st-andrews.ac.uk/HistTopics/Time_1.html

» A Walk Through Time    An illustrated history of timekeeping from ancient times to the present.    http://physics.nist.gov/GenInt/Time/time.html

» Countdown    Calculate the exact time in days, hours, minutes and seconds from now until your birthday or any other event.    http://www.spiders.com/portfolio/demos/countdown/

» Daylight Saving Time    Why do we use daylight savings time and who invented it?    http://www.mrdowling.com/601-daylight.html

» Discover Magazine: Time Machine    Article explores a clock designed to keep accurate time for 10,000 years.    http://discovermagazine.com/2005/nov/cover

» How Stuff Works: Time    Complete five-part explanation of time and how it is measured, including information about clocks, time zones, and calendars.    http://www.howstuffworks.com/time.htm

» Industrious Clock    Clock using video of a hand drawing to display the time.    http://yugop.com/ver3/stuff/03/fla.html

» International Standard Date and Time Notation    International Standard ISO 8601 specifies numeric representations of date and time. It helps to avoid confusion caused by the many different national notations.    http://www.cl.cam.ac.uk/~mgk25/iso-time.html

» Latitude and Longitude    Introduction to latitude and longitude, a way of calculating exactly where you are anyplace on earth and a way to tell time.    http://www-spof.gsfc.nasa.gov/stargaze/Slatlong.htm

» Local Times Around the World    Find out what time it is anywhere in the world.    http://www.timeanddate.com/worldclock/

» Make Your Own Star Clock    Learn how to tell time by finding constellations in the night sky.    http://www.lhs.berkeley.edu/StarClock/starclockprintout.html

» Making a Horizontal Sundial    Learn how to make a sundial. Instructions are for beginners, intermediate, or advanced, and work for either the northern or southern hemispheres.    http://www.lmsal.com/YPOP/Classroom/Lessons/Sundials/sundials.html

» Making a Sun Clock    Before there were clocks, people used shadows to tell time. Learn how to make your own sun clock!    http://www.exploratorium.edu/science_explorer/sunclock.html

» NPR : 'Seize the Daylight'    Talks about the complicated politics and curious history of daylight standard time.    http://www.npr.org/templates/story/story.php?storyId=4572036

» National Geographic Kids Magazine: Water Clock Experiment    Demonstrates how water clocks can be used to keep time.    http://www.nationalgeographic.com/ngkids/trythis/try10.html

» On Time    Learn about the history of time measuring devices in this online Smithsonian Institute exhibit. Page discusses how the accuracy of watches and clocks affected people's perception and usage of time.    http://americanhistory.si.edu/ontime/

» Science Museum - Atomic Clocks    Talks about how different types of atomic clocks work, and the history of their invention.    http://www.sciencemuseum.org.uk/onlinestuff/stories/atomic_clocks.aspx

» The Galileo Project - Pendulum Clock    Describes Galileo's work on pendulums and the pendulum clock.    http://galileo.rice.edu/sci/instruments/pendulum.html

» The Hourglass    The University of Houston College of engineering, describes how an hourglass works and also provides interesting facts about this timekeeper.    http://www.uh.edu/engines/epi1469.htm

» Time    Just how do we measure time and what has Greenwich England got to do with it?    http://www.mrdowling.com/601-time.html

» Time Travel    Is time travel possible? See what Carl Sagan and Einstein had to say about time travel in this NOVA special.    http://www.pbs.org/wgbh/nova/time/

» US Library of Congress - How does an hourglass measure time?    Answers questions about how an hourglass keeps time and what are the contributing factors determining how long an hourglass lasts.    http://www.loc.gov/rr/scitech/mysteries/hourglass.html

» What Time Is It!    Gives the current time, synchronized by NIST. Close to 100 different time zones supported, as well as the ability to select the default time zone.    http://www.whattimeisit.com/

» When Does Daylight Savings Time Occur    Explanation of when and why we have daylight savings time.    http://www.logan.ws/articles/when_does_daylight_savings_time_occur.asp

» World Time Converter    Provides online times converter and brief information about GMT/UTC.    http://www.gkindia.com/bitsol_time/