Time
How do we measure time?
When was 3,000,000 years
ago?
What is a timeline?
Time
Units of Measurement
UNIT
SIZE
Second
Minute
60 seconds
Hour
60 minutes
UNIT
SIZE
Year
12 months
Olympiad
4 years
Lustrum
5 years
Decade
10 years
Indict
15 years
Generation
25 years
Day
24 hours
Week
7 days
Fortnight
14 days, 2 weeks
Century
100 years
Month
Between 28 and 31 days
Millennium
1000 years
Quarter
3 months
Epoch, Period, Era, Eon
Time
Geological Time
Cultural Time
Cambrian
Pre-history
Ordovician
Old Stone Age
Silurian
New Stone Age
Devonian
Ancient
Carboniferous
Classical
Permian
Middle Ages
Triassic
Modern
Jurassic
Industrial
Cretaceous
Tertiary
Time
Technological Time
Paleolithic
Mesolithic
Neolithic
Copper
Bronze
Iron
Steel
Computer
2,000,000 years ago
10,000 years ago
8,000 years ago
7,000 years ago
5,500 years ago
3,200 years ago
200 years ago
60 years ago
Time
January 1, 2000
Time
Calendar
Date
Gregorian
January 1, 2000
Babylonian
Year 2749
Buddhist
Year 2544
Chinese
Cycle 78, year 16 (Ji-Mao), month 11 (Wu-Yin), day 25 (Wu-Wu)
Egyptian
Year 6236
Ethiopian
23 Takhsas 1993
French
Décade II, Duodi de Nivôse de l'Année 208 de la Révolution
Greek
22 Kiyahk 1716
Hebrew
23 Teveth 5760
Islamic
24 Ramadan 1420
Julian
19 December 1999
Mayan
Long count = 12.19.6.15.0; tzolkin = 9 Ahau; haab = 8 Kankin
Persian
11 Dey 1378
Time
Why????
Calendar
Dating point
Hebrew
Creation of world
Islamic
Year of the hijira
French
Date of French Revolution
North Korea
Birth of Kim Il-Sung
Buddhist
Birth of Sidhartha
Western culture
??????????
Time
Dionysius Exiguus “Dennis the
Little (Humble)” 470-544
•Future dates on which Easter would fall
•"the consulship of Probus Junior [Flavius
Probus]“
•"since the incarnation [conception] of our
Lord Jesus Christ“
•25 March 1 AD
•'Anno Domini Nostri Iesu Christi' ('In the
Year of Our Lord Jesus Christ')
Time
Anno Domini
“In the Year of our Lord”
Before Christ
A. D.
B. C.
Before the Common Era
The Common Era
B. C. E.
C. E.
B. C. = B. C. E.
A. D. = C. E.
Time
Timeline
•A representation or exhibit
•key events
•within a particular historical period,
•often consisting of illustrative visual material
•accompanied by written commentary,
•arranged chronologically.
Time
oldest
end point
most recent
end point
Time
300
200
BC/BCE
100
0
100
200
AD
300
Time
11,000 BC
10,000 BC Neolithic Revolution
5000 BC
3100 BC Upper and Lower Egypt United
2670 BC First Dynasty of Ur
2500 BC Mohenjo-Daro
1000 BC
2000 BC Minoans and Myceneans
1500 BC Shang Dynasty
0
500 AD
1000 AD
1300 AD
753 BC Founding of Rome
476 AD Fall of the Roman Empire
1066 AD Norman Invasion of England
1215 AD Signing of the Magna Carta
Time
Time
Time
Centuries = 100 years
300
200
BC/BCE
100
0
100
200
AD
300
Time
Centuries = 100 years
300
200
BC/BCE
First century BC
100
0
100
200
AD
Second century AD
300
Time
160 BC
Which century BC?
300
200
3rd
100
2nd
BC/BCE
0
100
200
1st
AD
160 BC = 2nd century BC
300
Time
280 AD
Which century AD?
300
200
100
0
100
1st
BC/BCE
200
2nd
AD
280 AD = 3rd century AD
300
3rd
Time
Rule for aligning dates to the correct century
Add 1 to the 100’s
number
160
280
1492
2007
+1
+1
+1
+1
2
3
15
21
15th century
21 century
2nd century
3rd century
Time
3rd century BC
Which years BC?
300
200
3rd
100
2nd
BC/BCE
0
100
200
1st
AD
3rd century BC = Years 201 - 300 BC
300
Time
Rule for aligning centuries with
the correct date
Subtract 1 from the 100’s and add
the years 01 through 00
Time
The Roman Empire fell in the fifth century AD.
The Magna Carta was signed in the thirteenth
century AD.
501
1301
-1
-1
4
12
401 to 500 years
1201 to 1300 years
Time