China's CCTV made a short documentary about the sport of badminton. It is a pretty interesting clip to watch where Part 1 talks about the science and evolution of badminton racquet from the 60's onwards.
Yonex has been monopolizing the badminton racquet market and still does. New competitors have come and go over the years without much success. Introducing Li Ning, a brand that shows great potential to challenge Yonex.
Part 2 of this short documentary continues to explain the different designs of racquet to suit different styles of player.