Grebes (/ˈɡriːbz/) are aquatic diving birds in the order Podicipediformes  (/ˌpɒdɪsɪˈpɛdɪfɔːrmiːz/).[1] Grebes are widely distributed freshwater  birds, with some species also found in marine habitats during migration and winter. Most grebes fly, although some flightless species exist, most notably in stable lakes. The order contains a single family, the Podicipedidae, which includes 22 species in six extant genera.