The Wage-labor reference article from the English Wikipedia on 24-Apr-2004
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Wage-labor

Helping orphans the way you would do it
A wage-laborer is defined in the context of social theory as a person without ownership of the means of production, whose role in the market is to sell their own services (i.e., their labour) to those who do.

By definition, wage-laborers are supposed to be a unique feature of industrialized society, whereas earlier forms of social production entailed serfdom or slavery.