Medical Coding is the process of converting patient health information into alpha numeric codes. Coders take medial reports from doctors, which may include a patients condition, the doctors diagnosis, a prescription, and whatever procedures the doctor or healthcare provider performed on the patient, and turn that into a set of codes, which make up a crucial part of the medical claim.Medical Coding is the process of converting patient health information into alpha numeric codes. Coders take medial reports from doctors, which may include a patients condition, the doctors diagnosis, a prescription, and whatever procedures the doctor or healthcare provider performed on the patient, and turn that into a set of codes, which make up a crucial part of the medical claim.