Of many planes, some of the best we're produced in World War one. There's a reason it was called "The Great War". It gave us the sychronized machine gun, both Light and Medium. It also gave us the Fokker line too. Still to this day, there is Fokker planes flying around (passenger planes of course). The Fokker line was started by Anthony Fokker, after that most planes designed by other men. Here is a link to another wiki site:

This page shows the history and evolution of the Fokker line.