Medical coding and billing involves assigning codes to medical diagnoses, procedures, and services according to standardized classification systems. ICD-9 is the International Classification of Diseases, 9th Revision, which is the coding system used to classify diseases and a range of signs, symptoms, abnormal findings, complaints, social circumstances, and external causes of injury or disease. This document appears to be about a course related to medical coding and billing using the ICD-9 coding system.