Period It is a term that comes from the Latin word periodus which, in turn, has a background in the Greek language. It is important to note that period can also be written and pronounced as period , both forms being accepted by the Royal Spanish Academy (RAE) .
The notion is associated with weather and to different lapses or time cycles . It can be understood as a period to temporary extension of one thing or at term that something is taken to return to its original state.
For example: "The football matches are divided into two periods of forty-five minutes each", "We are living the longest period of economic growth in our history", "The director got the necessary support to be re-elected for a new term at the head of the institution".
From these general meanings, the term period can be found in different fields and with more or less diverse meanings. For the chemistry , a period is any of the horizontal lines found in the call periodic table of elements .
In the field of astronomy , the phase that takes a celestial body to complete an orbit is called orbital period . It is possible to distinguish between synodic periods (how long does it take body in appearing again in an astronomical point, being observed from our planet and regarding Sun) and the sidereal periods (the body's delay in completing a full circle around the sun, considering a certain star as a reference).
This term can also be used to refer to the menstrual cycle (the menstruation ) in the women and the females of certain animals: "I am somewhat uncomfortable since I have the period".
Periods of history
While dividing the history in periods it is necessarily arbitrary, since the human being knows only a part of his time on Earth, historians decided to establish the year 3000 a. C. as the beginning of the story, based on the fact that it was then that some Mesopotamian civilizations developed writing. Everything that happened until that moment belongs to the Prehistory and it is divided into Paleolithic (2 and a half million years before, period in which the human being appeared), Mesolithic and Neolithic.
Taking up the story from the year 3000 a. C., four periods were defined, which are the following:
Old age: started along with the invention of the writing and lasted until the Roman Empire fell in the West. Among its most outstanding features are maritime and agricultural activity, social and governmental organization. Some of the most important civilizations of this period were Roman, Ancient Greece, Mesopotamia and Ancient Egypt;
Middle Ages: it is the period that began with the fall of the Roman Empire of the West, in the year 476, and that ended in 1492 along with the discovery of America. There are scholars who prefer the closing of this stage in 1453, when the invention of the printing, the fall of the Eastern Roman Empire and the end of the 100-year war. One of the most important features of the Middle Ages was, in Europe, the development of feudalism;
Modern age: was characterized by the end of feudalism, the developing of the bourgeoisie and capitalism, and the creation of modern states. This period ended together with the French Revolution, in the year 1789;
Contemporary age: Depending on the point of view, it could be said that this is the period that we can best know, given that it continues today. Some of its main features are the advances at an artistic, technological level, Social, economic and political, with a clear focus on the so-called consumer society.