Oxygen masks are devices designed to deliver oxygen to individuals who may have difficulty breathing. They are commonly used in emergencies, such as during airplane flights or in medical situations. The mask fits over the nose and mouth, allowing the user to inhale oxygen from a connected supply. In airplanes, oxygen masks are deployed when cabin pressure drops, ensuring passengers receive adequate oxygen. In medical settings, they help patients with respiratory issues, such as those suffering from asthma or COPD. Proper use of oxygen masks can be crucial for maintaining oxygen levels in the body.