Medical coding and billing are often lumped together as one job. However, a certified coder is a separate person than a professional biller. A coding specialist handles the details of placing exact codes on the claim so that the physician office enjoys maximum reimbursement. In addition, the qualities of an ideal biller are different than those of an expert coder. Both coders and billers must be familiar with the necessary coding protocols, such as ICD-10, CPT, and HCPCS.