The terms refer to the work force of the 1920s. "White-collar" workers had jobs in offices and "blue-collar" workers had jobs in factories. google "what is the difference between a white-collar worker and a blue-collar worker?" https://smallbusiness.chron.com/bluecollar-worker-whitecollar-worker-11074.html Both terms came into common use in the 1920s, with novelist Upton Sinclair credited with coining the term “white-collar” to denote those workers who performed administrative or clerical work. More than a collar put blue-collar workers in a separate category; so did their entire work uniform. As construction workers, loggers, mechanics, carpenters and factory assemblymen, they wore overalls, jeans or durable work shirts – mostly in the color blue, to more easily cover the dust and dirt they inevitably came into contact with.

Hi Daniela, These are terms in (particularly American) English used to talk about the kind of job someone has — whether the job requires a university degree or not, whether it is done in a factory or in an office, and how much physical work it takes. A white collar job (traditionally) requires a university degree and sitting behind an office desk. A blue collar job (traditionally) needed a high school diploma only and took place in a factory with a lot of physical work. Americans prefer to talk about class in very indirect ways, and this is one example. Someone is a type of worker because of what type of job they do.

Another thing that separates the two is the attitude that people had about the people working in those types of jobs. White-collar workers typically obtained a higher education level than the Blue-collar workers. This resulted in a division because of pride and the feeling of entitlement among the White-collar workers.

Blue-collar worker - jobs that include manual labor and manufacturing White-collar worker - business professionals office jobs.