Roof prisms are optical devices used in binoculars and other optical instruments to invert and revert images. They consist of two prisms arranged in a specific way, allowing light to pass through while maintaining the correct orientation of the viewed image. This design is essential for providing a right-side-up view, making it easier for users to observe distant objects. The most common types of roof prisms are the Porro prism and the Dach prism. Roof prisms are compact and lightweight, making them ideal for portable devices. Their design contributes to the slim profile of binoculars, enhancing their usability for outdoor activities like birdwatching and hiking.