While there are hundreds of different mask options, there are three main types of sleep apnea machines. There’s the previously mentioned CPAP or continuous positive airway pressure machine. This machine uses a constant flow of air pressure throughout the night. When the wearer exhales, they are exhaling against the incoming pressure.
An APAP machine is an automatic positive airway pressure machine. These are automated to work within a pre-set range. They adjust throughout the night to fit your pressure needs breath by breath.
A BiPAP is a bi-level positive airway pressure machine. It offers two levels of airway pressure, one for inhalation and the other for exhalation. These are often used for those who have severe OSA.