Flight or flying is a process of
An aerostat is a system that remains in the air primarily through the use of floating to give an aircraft that has the same overall density as air. Aerostats include free balloons, airships, and moored balloons. An aerostat's main structural component is its envelope, a lightweight skin containing a lifting gas to provide floating, to which other components are attached.
Aerostats are so named because they use "aerostatic" lift, a buoyant force that does not require lateral movement through the surrounding air mass. By contrast, aerodynes primarily use aerodynamic lift, which requires the side movement of at least some part of the aircraft through the surrounding