OIS, or Optical Image Stabilization, is a technology used in cameras and smartphones to reduce blurriness caused by small movements during photography or videography. It works by adjusting the lens or image sensor to counteract any shaking or vibrations, resulting in clearer images and smoother videos. This feature is particularly beneficial in low-light conditions or when using zoom, where even slight movements can lead to noticeable blur. Many modern devices, including DSLR cameras and smartphones, incorporate OIS to enhance image quality and improve the overall user experience in capturing photos and videos.