<P> In many countries (such as Australia, Canada, Denmark, France, New Zealand, United Kingdom, and United States), a white - collar worker is a person who performs professional, managerial, or administrative work . White - collar work may be performed in an office or other administrative setting . Other types of work are those of a blue - collar worker, whose job requires manual labor and a pink - collar worker, whose labor is related to customer interaction, entertainment, sales, or other service - oriented work . Many occupations blend blue, white and pink (service) industry categorizations . </P> <P> The term refers to the white dress shirts of male office workers common through most of the nineteenth and twentieth centuries in Western countries, as opposed to the blue overalls worn by many manual laborers . </P> <P> The term "white collar" is credited to Upton Sinclair, an American writer, in relation to contemporary clerical, administrative, and management workers during the 1930s, though references to white - collar work appear as early as 1935 . </P>

Where did white collar and blue collar come from
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