Snoring and Obstructive Sleep Apnea (OSA) are breathing disorders, which occur during sleep, due to the narrowing or total closure of the airway.
OSA
...is when the airway becomes completely blocked and breathing stops. The brain then detects the lack of oxygen and prompts a momentary arousal to draw breath. Although OSA sufferers may experience hundreds of apnea episodes per night, they are unlikely to remember any of them. In fact, if the sufferer lives alone or sleeps separately they may not be aware of their condition, even after many years.