Century

Template:Short description Template:Other uses A century is a period of 100 years or 10 decades. Centuries are numbered ordinally in English and many other languages. The word century comes from the Latin centum, meaning one hundred. Century is sometimes abbreviated as c.<ref>Template:Cite web</ref>

A centennial or centenary is a hundredth anniversary, or a celebration of this, typically the remembrance of an event which took place a hundred years earlier.

Start and end of centuries

Although a century can mean any arbitrary period of 100 years, there are two viewpoints on the nature of standard centuries. One is based on strict construction, while the other is based on popular perception.

According to the strict construction, the 1st century AD, which began with AD 1, ended with AD 100, and the 2nd century with AD 200;Template:NoteTag in this model, the n-th century starts with a year that follows a year with a multiple of 100 (except the first century as it began after the year 1 BC) and ends with the next coming year with a multiple of 100 (100n), i.e. the 20th century comprises the years 1901 to 2000, and the 21st century comprises the years 2001 to 2100 in strict usage.<ref>Template:Cite web</ref>

In common perception and practice, centuries are structured by grouping years based on sharing the 'hundreds' digit(s). In this model, the n-th century starts with the year that ends in "00" and ends with the year ending in "99";<ref>Template:Cite web</ref> for example, in popular culture, the years 1900 to 1999 constitute the 20th century, and the years 2000 to 2099 constitute the 21st century.<ref>Template:Cite web</ref> (This is similar to the grouping of "0-to-9 decades" which share the 'tens' digit.)

To facilitate calendrical calculations by computer, the astronomical year numbering and ISO 8601 systems both contain a year zero, with the astronomical year 0 corresponding to the year 1 BC, the astronomical year -1 corresponding to 2 BC, and so on.<ref>Template:Cite web</ref><ref>Template:Cite web</ref>

Strict vs Popular usage

Year	2 BC	1 BC	1	2	...	99	100	101	102	...	199	200	201	202	...	1899	1900	1901	1902	...	1999	2000	2001	2002	...	2025	...	2099	2100	2101	2102	...
Strict	1st century BC		1st century					2nd century					3rd century		...	19th century		20th century					21st century							22nd century		...
Popular	1st century BC		1st century				2nd century					3rd century			...	19th century	20th century					21st century							22nd century			...

Alternative naming systems

Template:Unreferenced section Informally, years may be referred to in groups based on the hundreds part of the year. In this system, the years 1900–1999 are referred to as the nineteen hundreds (1900s). Aside from English usage, this system is used in Swedish, Danish, Norwegian, Icelandic, Finnish and Hungarian. The Swedish Template:Lang (or Template:Lang), Danish Template:Lang (or Template:Lang), Norwegian Template:Lang (or Template:Lang),<ref>Template:Citation</ref> Finnish Template:Lang (or Template:Lang) and Hungarian Template:Lang (or Template:Lang) refer unambiguously to the years 1900–1999. In Swedish, however, a century is in more rare cases referred to as Template:Lang ("the n-th century") rather than Template:Lang, i.e. the 17th century is (in rare cases) referred to as Template:Lang rather than 1600-talet and mainly also referring to the years 1601–1700 rather than 1600–1699;<ref>Template:Cite web</ref> according to Svenska Akademiens ordbok, Template:Lang may refer to either the years 1501–1600 or 1500–1599.<ref>Template:Cite web</ref>

Similar dating units in other calendar systems

While the century has been commonly used in the West, other cultures and calendars have utilized differently sized groups of years in a similar manner. The Hindu calendar, in particular, summarizes its years into groups of 60,<ref>Template:Cite web</ref> while the Aztec calendar considers groups of 52.<ref>Template:Cite web</ref>

See also

• Age of Discovery
• Ancient history
• Before Christ and Anno Domini
• Common Era
• Decade
• List of decades, centuries, and millennia
• Lustrum
• Middle Ages
• Millennium
• Modern era
• Saeculum
• Year

Bibliography

• The Battle of the CenturiesTemplate:Dead link, Ruth Freitag, U.S. Government Printing Office. Available from the Superintendent of Documents, P.O. Box 371954, Pittsburgh, PA 15250- 7954. Cite stock no. 030-001-00153-9. Retrieved 3 March 2019.