When someone gives mouth to mouth resuscitation they are said the be ventilating the person's lungs. what does this mean?

Ventilating the lungs refers to the process of delivering air into a person's respiratory system to help them breathe when they are unable to do so on their own. During mouth-to-mouth resuscitation, the rescuer blows air into the person's mouth, allowing oxygen to enter the lungs and carbon dioxide to be expelled. This is crucial in emergencies, such as cardiac arrest, to maintain oxygen supply to vital organs until professional help arrives.