What were the two basic types of industrial workers in the united states in the 1800s? why did one type of worker tend to earn higher wages

In the 1800s the United States had to two types of industrial workers, these were:

Craft workers were workers who had a specific set of skills and training while Common laborers were workers that lacked any kind of specialized training.

The main difference between these two was that Craft workers earned more and had more control over their working hours because of their skillset than the common laborer.  

united states reinforcements contributed greatly to three allied victories in france at: cantigny (first major american battle), argonne (the largest in the united states military history, involving 1.2 million american soldiers), and château-thierry (one of the first actions under general pershing).