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Decade
A decade () is a period of ten years. Decades may describe any ten-year period, such as those of a person's life, or refer to specific groupings of calendar years. Usage Any period of ten years is a "decade". For example, the statement that "during his last decade, Mozart explored chromatic harmony to a degree rare at the time" merely refers to the last ten years of Wolfgang Amadeus Mozart's life without regard to which calendar years are encompassed. Also, 'the first decade' of a person's life begins on the day of their birth and ends at the end of their 10th year of life when they have their 10th birthday; the second decade of life starts with their 11th year of life (during which one is typically still referred to as being "10") and ends at the end of their 20th year of life, on their 20th birthday; similarly, the third decade of life, when one is in one's twenties or 20s, starts with the 21st year of life, and so on, with subsequent decades of life similarly described by re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Year
A year or annus is the orbital period of a planetary body, for example, the Earth, moving in its orbit around the Sun. Due to the Earth's axial tilt, the course of a year sees the passing of the seasons, marked by change in weather, the hours of daylight, and, consequently, vegetation and soil fertility. In temperate and subpolar regions around the planet, four seasons are generally recognized: spring, summer, autumn and winter. In tropical and subtropical regions, several geographical sectors do not present defined seasons; but in the seasonal tropics, the annual wet and dry seasons are recognized and tracked. A calendar year is an approximation of the number of days of the Earth's orbital period, as counted in a given calendar. The Gregorian calendar, or modern calendar, presents its calendar year to be either a common year of 365 days or a leap year of 366 days, as do the Julian calendars. For the Gregorian calendar, the average length of the calendar year (t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anno Domini
The terms (AD) and before Christ (BC) are used to label or number years in the Julian and Gregorian calendars. The term is Medieval Latin and means 'in the year of the Lord', but is often presented using "our Lord" instead of "the Lord", taken from the full original phrase "''anno Domini nostri Jesu Christi''", which translates to 'in the year of our Lord Jesus Christ'. The form "BC" is specific to English and equivalent abbreviations are used in other languages: the Latin form is but is rarely seen. This calendar era is based on the traditionally reckoned year of the conception or birth of Jesus, ''AD'' counting years from the start of this epoch and ''BC'' denoting years before the start of the era. There is no year zero in this scheme; thus ''the year AD 1 immediately follows the year 1 BC''. This dating system was devised in 525 by Dionysius Exiguus, but was not widely used until the 9th century. Traditionally, English follows Latin usage by placing the "AD" abbr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Units Of Time
A unit of time is any particular time interval, used as a standard way of measuring or expressing duration. The base unit of time in the International System of Units (SI) and by extension most of the Western world, is the second, defined as about 9 billion oscillations of the caesium atom. The exact modern SI definition is "he secondis defined by taking the fixed numerical value of the cesium frequency, , the unperturbed ground-state hyperfine transition frequency of the cesium 133 atom, to be 9 192 631 770 when expressed in the unit Hz, which is equal to s−1." Historically, many units of time were defined by the movements of astronomical objects. * Sun-based: the year was the time for the Earth to revolve around the Sun. Historical year-based units include the Olympiad (four years), the lustrum (five years), the indiction (15 years), the decade, the century, and the millennium. * Moon-based: the month was based on the Moon's orbital period around the Earth. * Earth-based: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Year
A year or annus is the orbital period of a planetary body, for example, the Earth, moving in its orbit around the Sun. Due to the Earth's axial tilt, the course of a year sees the passing of the seasons, marked by change in weather, the hours of daylight, and, consequently, vegetation and soil fertility. In temperate and subpolar regions around the planet, four seasons are generally recognized: spring, summer, autumn and winter. In tropical and subtropical regions, several geographical sectors do not present defined seasons; but in the seasonal tropics, the annual wet and dry seasons are recognized and tracked. A calendar year is an approximation of the number of days of the Earth's orbital period, as counted in a given calendar. The Gregorian calendar, or modern calendar, presents its calendar year to be either a common year of 365 days or a leap year of 366 days, as do the Julian calendars. For the Gregorian calendar, the average length of the calendar year (t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Millennium
A millennium (plural millennia or millenniums) is a period of one thousand years, sometimes called a kiloannum (ka), or kiloyear (ky). Normally, the word is used specifically for periods of a thousand years that begin at the starting point (initial reference point) of the calendar in consideration (typically the year "1") and at later years that are whole number multiples of a thousand years after the start point. The term can also refer to an interval of time beginning on any date. Millennia sometimes have religious or theological implications (see millenarianism). The word ''millennium'' derives from the Latin ', thousand, and ', year. Debate over millennium celebrations There was a public debate leading up to the celebrations of the year 2000 as to whether the beginning of that year should be understood as the beginning of the “new” millennium. Historically, there has been debate around the turn of previous decades, centuries, and millennia. The issue arises from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
