Mouth to mouth resuscitation is a term used in emergency medical situations where a person is not breathing and requires immediate assistance. The term, however, has various synonyms that can be used interchangeably. These include rescue breathing, artificial respiration, and pulmonary resuscitation. Some people may also use the term mouth-to-nose resuscitation, which involves breathing air into a person's nose instead of their mouth. Another synonym is cardiopulmonary resuscitation (CPR), which involves a combination of chest compressions and artificial respiration. No matter the term used, the primary goal is to restore breathing and oxygen supply to the brain.