Strata - unit of division in the stratification.Since the very concept came from geology, the stratum - a stratum layer, not in the ground, and in the community.All the people in one way or another, belong to different social groups.They can distinguish an infinite number, if we take the basis of different principles of division.

For example, you can select strata depending on the age, material wealth, ownership of property.Professional musician, amateur musician, a listener - will also be a kind of layers.In different historical periods, in different states such division could play a significant role in the lives of all people.So, India was caste in Russia - class, at a later period - classes.Belonging to one or another group could determine the person's life, from birth to death.In India, the same transition from one caste to an
other was impossible.In Russia, with great difficulty and luck you can "climb" up the social ladder.But the rise of the wealthy merchant class in the peasantry, the petty bourgeoisie class was the only real closer to the XX century.

But now the stratification plays an important role in the social life of almost all people.Despite the proclamation of democratic principles, universal equality, in practice it appears that regard, financial situation, some of the activities allow to obtain certain privileges.And the society one way or another is divided into layers, lined up in the hierarchy.In general terms, it looks like the division between the elite and the masses.Ieat the bottom of the social ladder are, for example, ordinary workers, higher - officials who can influence them, are even higher - the ruling elite of the city, region, country, etc.

division into layers can be carried out and "horizontal", for example, by occupation.The well-known musician and a famous athlete can stand on the same rung of the "vertical" hierarchy, but they, of course, belong to different social groups.