Alcyonacea is an order of marine invertebrates commonly known as soft corals. Unlike hard corals, soft corals do not produce a rigid calcium carbonate skeleton. Instead, they have a flexible structure made of a protein called gorgonin, allowing them to sway with ocean currents. Soft corals can be found in various marine environments, often forming colorful colonies that provide habitat for diverse marine life. These organisms are primarily found in warm, shallow waters, particularly in tropical and subtropical regions. Alcyonacea includes species such as sea fans and sea whips, which play a crucial role in reef ecosystems. They contribute to biodiversity and provide shelter for fish and other marine organisms.