The Air Nomad is a peaceful nation who had placed on the top of mountains. The Air Nomads are fulled by all airbenders, male and female. The Council of Elders, their leaders was placed in the main temple.
Long ago, the people who discovered airbending from the flying bison fled to the mountain, the most peaceful and quiet place. Firstly, only airbender who can reach the temple. And, they lived happily, and trains the Avatar in airbending.
All of these Air Nomads are airbender. They will get their own arrow, if mastered all of 36 airbending moves.