Collar workers

Groups of working individuals are typically classified based on the colors of their collars worn at work; these can commonly reflect one's occupation or sometimes gender.White-collar workers are named for the white-collared shirts that were fashionable among office workers in the early and mid-20th century. Blue-collar workers are referred to as such because in the early 20th century, they usually wore sturdy, inexpensive clothing that didn't show dirt easily, such as blue denim or cambric shirts. Various other "collar" descriptions exist, as well.

The term "white-collar worker" was coined in the 1930s by Upton Sinclair, an American writer who referenced the word in connection to clerical, administrative and managerial functions during the 1930s. A "white-collar worker" is a salaried professional, typically referring to general office workers and management. However, in certain developed countries like the United States, the United Kingdom, and Canada, a person is assumed to be a white-collar worker when one engages in a highly professional and successful career or works in either an administrative or managerial role.

A blue-collar worker is a member of the working class who performs manual work and either earns an hourly wage or is paid piece rate for the amount of work done. This term was first used in 1924.

A green-collar worker is a worker who is employed in the environmental sectors of the economy. Environmental green-collar workers (or green jobs) satisfy the demand for green development. Generally, they implement environmentally conscious design, policy, and technology to improve conservation and sustainability. Formal environmental regulations as well as informal social expectations are pushing many firms to seek professionals with expertise with environmental, energy efficiency, and clean renewable energy issues. They often seek to make their output more sustainable, and thus more favorable to public opinion, governmental regulation, and the Earth's ecology.

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