High Dynamic Range Imaging, or HDRI, is a technique used in photography and computer graphics to capture a wider range of brightness levels than standard imaging methods. This allows for more detail in both the brightest and darkest areas of an image, creating a more realistic representation of scenes as the human eye perceives them. In 3D rendering and visual effects, HDRI is often used to create realistic lighting and reflections. By using HDR images as environment maps, artists can simulate how light interacts with objects, enhancing the overall quality and realism of the final render.