The oceanic zone is typically defined as the area of the ocean lying beyond the continental shelf (such as the Neritic zone), but operationally is often referred to as beginning where the water depths drop to below 200 meters (660 feet), seaward from the coast into the open ocean with its Pelagic zone. There are four ocean zones: the Sunlight zone, the Twilight zone, the Midnight zone, and the Abyssal zone.