Calendars and Concepts of Time

1. Aztec Calendar (2)
2. Babylonian Calendar (3)
3. Chinese Calendar (1)
4. Egyptian Calendar (1)
5. Greek Calendar (2)
6. Indian Calendar (4)
7. Numerals of the Calendar (1)
8. Roman Calendar (12)

Intercalation
Intercalation is a term referring to insertion into a calendar.

A.D. Anno Domini A.D.
A.D. is a Latin abbreviation for Anno Domini.

Calendar
Births, deaths, festivals, and other significant events from antiquity -- approximately -- since we use a different calendar from the ones used by the Greeks and Egyptians, and a modified version of the one used by the Romans.
March was the first month of the ancient Roman religious calendar. The month of March was sacred to the god Mars, father of the founder of Rome, Romulus.

Jewish Calendar Months
Names of the months of the Jewish calendar.

Ides, Kalends, Nones, and Pridie
The terminology used to divide the month in three parts was based on the first three lunar phases.

Two Jewish New Years
The Hebrew calendar is different from the Gregorian in that it is lunisolar and honors both a religious and a secular new year.

The Calendar
Lists the names for the Chinese years, compares the months in the Gregorian, Jewish, Islamic, and Hindu systems.

Calendars and Their History
By L. E. Doggett, reprinted from the Explanatory Supplement to the Astronomical Almanac.

A Walk Through Time
Ancient calendars, early clocks, and world time scales from the National Institute of Standards and Technology.