<P> Blue - collar work is often paid hourly wage - labor, although some professionals may be paid by the project or salaried . There is a wide range of payscales for such work depending upon field of specialty and experience . </P> <P> The term blue - collar stems from the image of manual workers wearing blue denim or chambray shirts as part of their uniforms . Industrial and manual workers often wear durable canvas or cotton clothing that may be soiled during the course of their work . Navy and light blue colors conceal potential dirt or grease on the worker's clothing, helping him or her to appear cleaner . For the same reason, blue is a popular color for boilersuits which protect a worker's clothing . Some blue collar workers have uniforms with the name of the business and / or the individual's name embroidered or printed on it . </P> <P> Historically the popularity of the color blue among manual labourers contrasts with the popularity of white dress shirts worn by people in office environments . The blue collar / white collar color scheme has socio - economic class connotations . However, this distinction has become blurred with the increasing importance of skilled labour, and the relative increase in low - paying white - collar jobs . </P> <P> The term blue collar was first used in reference to trades jobs in 1924, Alden, Iowa newspaper . </P>

Where did the term blue collar and white collar originated
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