双翅目 (Diptera) is an order of insects commonly known as flies. This group is characterized by having a single pair of wings, with the second pair reduced to small structures called halteres, which help with balance during flight. Diptera includes a wide variety of species, such as houseflies, mosquitoes, and fruit flies. Flies play significant roles in ecosystems, including pollination and decomposition. Some species are also important in medical research and agriculture, while others can be pests or vectors for diseases. Understanding the biology and behavior of 双翅目 is crucial for managing their impact on human health and the environment.