Pulse oximeters are non-invasive medical devices that play a crucial role in monitoring a patient's oxygen saturation levels (SpO2) and pulse rate. Typically clipped onto a fingertip, toe, or earlobe, these small, portable devices work by emitting light through the tissue and measuring the amount of light absorbed by oxygenated and deoxygenated hemoglobin. The results are displayed digitally, providing immediate and continuous readings. Pulse oximeters are vital for assessing respiratory function and are widely used in hospitals, clinics, and increasingly, in homes, especially for individuals with conditions such as asthma, chronic obstructive pulmonary disease (COPD), or during recovery from respiratory illnesses. They offer an early warning system for low oxygen levels, enabling timely intervention and significantly contributing to patient safety and effective management of respiratory conditions.