The document discusses calendars and their history. Early civilizations noticed regular patterns in the sun, moon, and seasons and developed calendars to track the passage of time. The most widely used modern calendar is the Gregorian calendar, a 12-month calendar developed in the 1580s. It is the standard calendar for most of the world today but there are also other calendars such as the Jewish, Chinese, Indian, and Islamic calendars.

1. The Calendar 2009 Information adapted from Millennium: An Interdisciplinary Investigation p. 22 and 24

2. What is a Calendar? A simple way to measure the passage of time Picture used from Google Images from ohjoy.blogs.com

3. Calendar Early people in history noticed time changes regularly Sun rises, Sun sets, moon changes, seasons

4. Calendar Many ancient civilizations made calendars Each one is different

5. The Gregorian Calendar 12 months Developed in the 1580’s by Pope Gregory XIII Most widely used calendar in the world Picture used from Google Images from parbeszed.com

6. The Gregorian Calendar This is not the only calendar http://www.webexhibits.org/calendars/calendar-jewish.html http://www.webexhibits.org/calendars/calendar-chinese.html http://www.webexhibits.org/calendars/calendar-indian.html http://www.webexhibits.org/calendars/calendar-islamic.html

7. The Gregorian Calendar Christian calendar Based on the birth of Jesus Christ Uses B.C. and A.D.

8. B.C. vs A.D. B.C. = Before Christ A.D. = Anno Domini Latin for “In The Year of Our Lord” B.C. counts down ( 10, 000 B.C. – 1 B.C.) A.D. counts up ( A.D. 1 – A.D. 2009)

9. Other Abbreviations B.C.E. – Before Common Era (same as B.C.) C.E. – Common Era (same as A.D.)