A professional crafter is an artist who generally works with materials not considered "fine art." They make hand-made crafts and sell them for profit.
Some examples of crafting include glass work, jewelry making, ceramins, weaving, and bookmaking. These are only a few examples, there are thousands more!
A professional crafter does not need a degree. However, knowledge in fine arts is recommended so crafters can make high-quality products. It also makes them seem more legitimate to consumers.
Many Universities and community colleges offer classes that focus on a certain craft. There are also crafting books a prospective crafter can read to self-teach themselves.