First, they are used as parachites
A flying disk moving through the air is considered mechanical motion because it is propelled by physical forces such as the initial throw and aerodynamic lift.
an Airship is an aircraft of the lighter-than-air type sustained in the air by gas an aeroplane in a mechanically propelled heavier-than-air flying machine
A plane, bird, rocket, frisbee, in fact anything that is propelled on a trajectory in air can be considered to be flying.
Ornithopter
To move through air or water means to travel or progress by displacing the air or water that surrounds the object. This could involve activities like swimming or flying, where the object is propelled through the medium of air or water.
There is debate as to what the first flying machine actually was. It looks to me that the first machine was either a bird-shaped jet-propelled object or a glider though... For more on the invention of the hot air balloon, check out: http://www.ideafinder.com/history/inventions/haballoon.htm
Rocket engines are not air breathing engines and hence they can be propelled into space.
Rocket propelled grenades
rocket propelled grenades
Rocket propelled grenades
rocket propelled grenades
In a well system, water is propelled by air pressure.