Calendrical Calculations -- Published by Cambridge University Press. Gives a unified algorithmic presentation of the Gregorian, ISO, Julian, Coptic, Ethiopic, & Islamic civil calendars. Visit

Lunisolar Calendar -- Lunar calendar with lunations, from new moon to new moon, instead of months. Moon phase on each day. Chinese, Jewish, & Islamic months. Eclipses, meteors, planets, star charts. Christian, Pagan, Islamic, Hindu, & Jewish holidays. Visit

World Holidays: Weeks & Months -- Information on the origin of the week, & etymology of month & weekday names. Visit

Astronomy by JavaScript: Sun Calculators & More -- Applets related to calendars & keeping time, including sidererial time. Visit

Julian Day Numbers -- An explanation of the Julian day number system used by astronomers & calendricists. Visit

ACalendar.com -- The calendar has many options with a standard monthly interface, including sunrise, sunset, and Moon phases. Visit

Britannica.com - Clockworks: From Sundials to the Atomic Second -- Britannica.com explores the history of timekeeping, from sundials to cesium atomic clocks. Visit

Calendars through the Ages -- History & FAQs of calendars, from ancient Rome to outer space. Including Julian, Gregorian, Jewish, Islamic, Chinese, and Mayan. Visit

Blue Moon Myths -- Second full moon in a month, or third full moon in a single season? Visit

Calendar Studies -- Articles on the Gregorian & Julian calendars, the ISO date format, the Julian day number system, the Maya calendar, the Goddess lunar calendar, the Liberalia Triday Calendar & C functions for date conversion; plus software for calendrical conversion. Visit

World Calendar/Clock, Appointments, Sun/Moon positions, Metric/Calendar Conversion -- PlexGlobe is a productivity toolkit for global users & businesses that includes: - World clock & calendar such as Chinese & so on. Visit

Millennium Mistake -- Explains the difference between millenium & year 2000 as the absence of a year zero. Visit

Time & Dates -- Information on date, time, and time zones from the New York Public Library. Visit

The Islamic Calendar -- The mathematics of the Islamic calendar in Singapore. Visit

Calendopaedia -- The Encyclopaedia of Calendars. Visit

The Julian & Gregorian Calendars -- Explanations of the Julian Calendar, the Gregorian Reform, the adoption of the Gregorian Calendar, the length of the tropical year & related matters. Visit

The Difference Between the Millennium & Year 2000 -- Questions & answers to satisfy the hearts of true millennium buffs. Visit

Astronomy & Space Calendar -- Features different views of the night sky, constellations, stars, planets, and other celestial wonders. Visit