]]Flight is the process by which an object achieves sustained movement either through the air (or movement beyond earth's atmosphere, in the case of spaceflight) by aerodynamically generating lift, propulsive thrust or aerostatically using buoyancy, .
The most successful groups of living things that fly are insects, birds, and bats. Each of these groups' wings evolved separately from different structures. See also Bird flight. Also successful were the extinct Pterosaurs, an order of reptiles contemporaneous with the dinosaurs.Bats are the only mammals capable of true flight. However, there are several gliding mammals which are able to glide from tree to tree using fleshy membranes between their limbs; some can travel hundreds of meters in this way with very little loss in height. Flying tree frogs use greatly enlarged webbed feet for a similar purpose, and there are flying lizard which employ their unusually wide, flattened rib-cages to the same end. Certain snakes als