There are some quality and skill differences between medical billers and medical coders. A biller, for example, requires a great deal of empathy, as they are often in contact with patients directly. They might have to explain why a medical bill is so high or why a patient was denied a claim. For this reason, communication is an important skill for medical billers. They'll be required to speak with insurance companies and healthcare employers to investigate and analyze bills.
Coders, on the other hand, require exceptional skills in memorization and analytics. They must interpret and memorize hundreds of codes that correlate to different medical procedures. For this reason, they are often very meticulous, technical thinkers with a strong aptitude for understanding data.