Book excerpt: Every known illness, disease and condition has a specific number that goes along with the word describing the person's medical problem. Every physician and their office staff must know medical codes for the sake of billing purposes. If the doctor and office staff does not code a specific illness, condition or disease correctly the insurance company may not pay for treatment, medication, in hospital stays, outpatient treatment, and a number of surgical and other procedures performed for the patient, making it impossible for the patient to receive the proper treatment. Common illnesses, diseases and conditions listed in a pamphlet would enable the medical student to become familiar and able to memorize with the more common medical codes. The bottom line for using proper ICD codes is money reimbursement for the medical community and patient.