Medical coding is the process of translating healthcare diagnoses, procedures, medical services, and equipment into standardized alphanumeric codes. These codes are derived from medical records, such as physician notes, lab results, and reports. It helps in billing, insurance claims, and maintaining patient records. Common coding systems include ICD (International Classification of Diseases), CPT (Current Procedural Terminology), and HCPCS (Healthcare Common Procedure Coding System). Accurate medical coding ensures proper reimbursement and compliance with regulations.