Flying

Flight is the process by which an object moves through space. This space can be atmospheric (such as air) or vacuum (in the case of spaceflight). The movement is usually caused by generating thrust of some sort, however the manner of elevation depends on what object is being flown. Below are some of the main types of flight:

Buoyant:

Buoyant flight takes place when the object flying is lighter than (or as light as) air itself. Through careful balancing, aerostat systems allow themselves the same overall density as air, which means that by slightly tweaking certain properties, the craft can move about at will. The main components of buoyant air systems are an envelope containing lifting gas, and a carriage for passengers. Aerostats are so named due to their use of aerostatic lift, which uses a buoyant force that does not require lateral movement through surrounding air masses.

Aerodynamic:

Aerodynamic flight is movement through the air which depends on the air being channeled around the object in a certain way. Through design (or evolution), an object will be tweaked to remain in the air for longer.

Aerodynamic flight can be seen in two categories, either as powered or non-powered. Powered flight uses a source of propulsion combined with aerodynamic design, which allows the object to be controlled at will. Non-powered flight relies solely on aerodynamic design and wind currents. Due to the lack of full control associated with non-powered flight, most forms of aerodynamic flight are powered. Some of the forces at play within powered aerodynamic flight can be seen below, these forces are adjusted to achieve steady flight. 

Within the world of flight there are naturally other objects which fly naturally as opposed to mechanically. Birds, insects, and bats are the only species which can fly by creating their own form of thrust, however there are other species which have evolved to glide and soar through the development of a more aerodynamic form. Animals such as flying squirrels have generated the ability to achieve non-powered flight.