Sandy has been going to Dr. Nobles since she was a young girl. Even though she doesn't live at home anymore, she still sees Dr. Nobles when she is sick. Today she is seeing him because she has an itchy rash on her arm.
Dr. Nobles is Sandy's primary care physician. He is sometimes called a family doctor or general practitioner. This means that he takes care of Sandy when she is sick. He also gives her an examination once a year to make sure she is staying healthy.
Today Dr. Nobles is stumped. He doesn't know why Sandy has a rash on her arm. He doesn't know what kind of rash it is or how to treat it. He refers Sandy to a dermatologist.
There are all kinds of doctors. They have different names. They treat different parts of your body. If your doctor can't tell what's wrong with you, he might refer you to a specialist.