Coastal structures are man-made constructions built along coastlines to protect against erosion, flooding, and storm damage. These structures include seawalls, jetties, breakwaters, and groins, each serving specific purposes to manage water flow and sediment movement. These structures help maintain the integrity of beaches and coastal areas, ensuring safety for nearby communities and preserving natural habitats. By controlling wave action and redirecting currents, coastal structures play a crucial role in coastal management and environmental protection.