Century

Century

A century is a period of 100 years. Centuries are numbered ordinally in English and many other languages. The word century comes from the Latin word centum, meaning one hundred. Centuries are important units of time in history, chronology, and astronomy.

Definition and Usage

A century is typically used to denote a period of 100 years in the Gregorian calendar. For example, the 20th century includes the years from 1901 to 2000, while the 21st century includes the years from 2001 to 2100. This system of numbering centuries is known as the Anno Domini (AD) system, which is used in the Gregorian calendar.

Historical Significance

Centuries are often used to categorize and study historical events. For instance, the 19th century is known for the Industrial Revolution, while the 20th century is marked by significant events such as the World Wars, the Cold War, and the Digital Revolution.

Astronomical Use

In astronomy, centuries are used to measure long periods of time. For example, the precession of the equinoxes is a slow movement of the Earth's axis that takes approximately 26,000 years to complete, or about 260 centuries.

Related Concepts

• Decade: A period of 10 years.
• Millennium: A period of 1,000 years.
• Epoch (reference date): A specific point in time used as a reference for dating events.

See Also

• Timeline
• Calendar era
• Historical period
• Chronology