Optical Image Stabilization (OIS) is a technology used in cameras and smartphones to reduce blurriness caused by camera shake. It works by using special lenses or sensors that can move to counteract any unwanted movements, ensuring that the captured image remains clear and sharp. This is especially useful in low-light conditions or when taking photos at longer focal lengths. OIS can be found in various devices, including digital cameras, smartphones, and camcorders. By stabilizing the image before it is captured, OIS helps photographers and videographers achieve better results without needing a tripod or other stabilizing equipment.