What type of unions were composed of skilled workers who were harder to replace?

Craft unions were organizations made up of skilled workers who specialized in a particular trade or craft. These unions focused on representing workers who had honed specific skills through training or apprenticeship, making them essential to their industries. Because of their specialized skills, members of craft unions were typically harder to replace compared to unskilled or semi-skilled workers, giving them greater bargaining power in negotiations with employers.

Craft unions played a significant role in advocating for better wages, working conditions, and job security, leveraging the fact that they possessed unique expertise that was not easily replicated. This emphasis on skilled labor distinguished them from other types of unions, such as industrial unions, which included both skilled and unskilled workers, or trade unions, which may encompass broader categories of a specific trade but do not necessarily imply the same level of specialization.