Calendar

A calendar is a tool for organizing days. People use calendars to say when something happened, and for planning things that have not happened yet. The calendar gives the days names and numbers, called calendar dates. The dates are usually made based on how things in the sky seem to move. The year and month are based on motions of the Sun and moon. By knowing what day something happened or will happen, people have an easier life. Since the beginning of history, knowing when the seasons would start for crops was very important for farmers.

2024 in other calendars

Gregorian calendar	2024 MMXXIV
Ab urbe condita	2777
Armenian calendar	1473 ԹՎ ՌՆՀԳ
Assyrian calendar	6774
Bahá'í calendar	180–181
Balinese saka calendar	1945–1946
Bengali calendar	1431
Berber calendar	2974
British Regnal year	2 Cha. 3 – 3 Cha. 3
Buddhist calendar	2568
Burmese calendar	1386
Byzantine calendar	7532–7533
Chinese calendar	癸卯年 (Water Rabbit) 4720 or 4660     — to — 甲辰年 (Wood Dragon) 4721 or 4661
Coptic calendar	1740–1741
Discordian calendar	3190
Ethiopian calendar	2016–2017
Hebrew calendar	5784–5785
Hindu calendars
- Vikram Samvat	2080–2081
- Shaka Samvat	1945–1946
- Kali Yuga	5124–5125
Holocene calendar	12024
Igbo calendar	1024–1025
Iranian calendar	1402–1403
Islamic calendar	1445–1446
Japanese calendar	Reiwa 6 (令和６年)
Javanese calendar	1957–1958
Juche calendar	113
Julian calendar	Gregorian minus 13 days
Korean calendar	4357
Minguo calendar	ROC 113 民國113年
Nanakshahi calendar	556
Thai solar calendar	2567
Tibetan calendar	阴水兔年 (female Water-Rabbit) 2150 or 1769 or 997     — to — 阳木龙年 (male Wood-Dragon) 2151 or 1770 or 998
Unix time	1704067200 – 1735689599

Calendar systems have a beginning time or era. The calendar era is often a religion-based event, such as the birth of Jesus, but it may be a political event such as a coronation or the founding of a state. Dates that are counted from the coronation are called "regnal".

The three principal calendars most used today are the Gregorian, Hebrew, and Islamic calendars. Other calendar systems from many different parts of the world are also used.

Basis

Calendars are based on three natural things:

1. The Earth turns all the way around its axis.
2. The Moon goes all the way around the Earth.
3. The Earth goes all the way around the Sun.

The Earth turns all the way around its axis about 24 hours. It is called the Solar Day. Days of most calendars are strongly based on the Solar Day.

The Moon turns all the way around the Earth about 29 days, 12 hours, 44 minutes and 2 seconds. Months of some calendars are still strongly based on the Moon. These are called Lunar calendars, which lasts about 354-355 days. Solar calendars ignore the moon, and depend entirely on the Sun.

The Earth goes all the way around the Sun in about 365 days, 5 hours, 48 minutes and 46 seconds. This is called the Solar year. Years of most calendars are strongly based on the Solar year.

Related pages

• Anno Domini (AD)
• Christian calendar
• Common Era (CE)
• Friday (Muslim)
• Saturday (Jewish)
• Sunday (Christian)
• Gregorian calendar (Christian)
• Hebrew calendar (Jewish)
• Islamic calendar (Muslim)

Other websites

• Calendar for many years, for many countries
• Calendar -Citizendium