1. A 'code' is a medical term for medical emergency. Codes are usually announced over the hospitals PA system and they are usually sent out through the paging system to the persons responsible for responding to such situations; typically MDs, PharmDs, respiratory therapists, RNs etc. Codes are usually announced when a patient is in imminent danger of dying, usually due to respiratory or cardiac arrest.
2. ACLS-Advanced Cardiac Life Support (ACLS) is et of clinical interventions for the urgent treatment of cardiac arrest and other life threatening medical emergencies, as well as the knowledge and skills to deploy those interventions.