Both belong to the category of sleep-disordered breathing. Simple snoring shows slight disturbances, in which breathing becomes very loud, but the upper airway is only partially blocked during sleep.
Snoring is a common symptom of obstructive sleep apnea. However, unlike mild snoring, sleep apnea is a serious medical condition because the airway is completely blocked during sleep and the patient completely stops breathing for 10 seconds or more. On one night, sleep apnea patients may experience hundreds of "apnea events" (or involuntary apneas). If your partner hears a silence interrupting a loud snoring and then buzzes or chokes sounds as you resume breathing, this pattern may indicate sleep apnea.