An oximeter is a medical device that measures the oxygen saturation in a person’s blood. It does so by emitting light through the skin, detecting the amount of oxygen in the blood based on the light absorption pattern. This non-invasive tool is commonly clipped onto a fingertip, and its results are crucial for assessing respiratory health, especially in conditions like COVID-19. Oximeters provide a quick and reliable way to monitor oxygen levels, aiding in the early detection of hypoxemia or low blood oxygen, a vital parameter for respiratory well-being.