Relations of production are the connections between people and property, that is, the ownership pattern, in the process of production. The ownership pattern determines the placement and role of classes — exploited and exploiters — in the process of production. The process of production consists of the division of labor, stage of development of technology, the level of deployed science and skills in shaping and defining the social organization of labor.
When productive forces and productive relations are compatible with one another, their interactivity causes more rapid development of the productive forces. The struggle between exploiting and exploited classes drives the mode of production through all its phases of development. When productive forces develop so as to become incompatible with the less mobile and more stagnant productive relations, the productive relations become fetters on production and hinder development of the productive forces. When qualitatively new productive forces, that is new machinery, arise in society, , the new machinery calls forth new forms of classes that express the new productive relations that correspond with the new productive forces. The new productive forces, new classes and new productive relations develop in antagonism with the old productive forces and its old corresponding productive relations. This dialectic of development occurs in every mode of production and is the motive force of history.
In the process of production, human beings work not only upon nature, but also upon one another. They produce only by working together in a specified manner and reciprocally exchanging their activities. In order to produce, they enter into definite connections and relations to one another, and only within these social connections and relations does their influence upon nature operate—i.e., does production take place.
. . . . The relations of production in their totality constitute what is called the social relations, society, and, moreover, a society at a definite stage of historical development, a society with peculiar, distinctive characteristics. Ancient society, feudal society, bourgeois (or capitalist) society, are such totalities of relations of production, each of which denotes a particular stage of development in the history of mankind.
(K. Marx, Wage, Labor and Capital, 1847.)
http://www.marxists.org/archive/marx/works/1847/wage-labor /ch05.htm
(See, Mode of production, Social relations of production.)
