An arch is a curved architectural structure that spans an opening and provides support to the weight above it. It is often characterized by its graceful curve and symmetrical design. Arches have been used in architecture for centuries and can be found in various forms, including Roman, Gothic, and Renaissance styles. They are not only functional but also add aesthetic appeal to buildings, lending a sense of grandeur and elegance. The arch symbolizes strength, stability, and the timeless beauty of architectural design.