- CPAP: snoring, sleep apnea syndrome.
- APAP: snoring, sleep apnea syndrome.
- BiPAP: mainly used for patients with lung disease, such as chronic obstructive pulmonary disease（COPD), Central sleep apnea (CSA), complex sleep apnea (CompSA), respiratory failure, bronchial asthma, respiratory disorders caused by neuromuscular diseases, etc.
Most of the mini portable PAP machines are of the APAP type, with few BiPAP.
For patients with only snoring or sleep apnea, CPAP is the best choice. It is not necessary to choose BiPAP. For some special patients with sleep apnea, doctors recommend using BiPAP. Because of obesity or other reasons, when using CPAP, apnea, the patient still experiences apnea. The pressure is not enough to fully open the airway, and provides less oxygen, leading that snoring or apnea still occurring. Its one-way pressure, compared with BiPAP's EPAP and IPAP, breathing is not so easy and the comfort degree is not better than BiPAP.