Fish of the order Heterosoma (Pleuronectiformes), including halibut, turbot, sole, plaice and flounders. Most live in the sea and many rank among the commercially valuable food fishes, prized for delicate white flesh. They are sold whole, as fillets, and processed into portions. Their flattened, asymmetric bodies — both eyes on the upper side — suit bottom-dwelling life, and the delicate flesh cooks in minutes, suiting gentle methods. Major fisheries target halibut, sole and plaice; sustainability varies by stock, with certification schemes guiding buyers, and the thin fillets demand careful handling to avoid gaping.