Drag is a force that acts opposite to the direction of movement of an airplane. Drag is mainly caused by air. The other forces that act on the plane while moving in the air are thrust, lift etc..
Drag effects paper airplane just as it affects anything else that moves. It is either parasitic or induced on paper airplanes. Drag may reduce a paper airplanes speed and/or range.
In aerodynamics, lift-induced drag, induced drag, vortex drag, or sometimes drag due to lift, is a drag force that occurs whenever a moving object redirects the airflow coming at it. This drag force...