Having only really known two designs for paper airplanes since my days as a child, one which flies about eight feet and another which flies about ten feet, I have always wondered how people manage to come up with designs that are able to fly much, much further than that. Clearly, these have no propulsion after their initial burst of energy (from being thrown); after that it's all about gliding.
So what design considerations should I make in order to create a plane that has the maximum flight time and distance? What are general best practices in this endeavor, and what are the physical bases for these choices?
I'm not looking for specific designs necessarily, but what qualities makes up a good paper airplane that can fly for a very long distance?