One hundred years before the series began, the Air Nomads were victims of genocide, by the Fire Nation and Fire Lord Sozin. Sozin saught to kill the Avatar, who had bee reborn into the Air Nomads, but ironically, he was the only one to survive.
Southern Air Temple
The Southern Air Temple was the childhood home of Avatar Aang. It was destroyed and it's people killed like the other Air Temples early on in the war by Fire Lord Sozin and his warriors in an attempt to kill the Avatar (Ironically, since he had run away a few weeks earlier, he was the only one who wasn't killed).
According to Aang, the Southern Air Temple is only accessable via a Flying Bison. The Southern Air Temple contains an Air Ball court (similar to football except you have to use Airbending and balance on poles to play), vast land (where Aang invented the air scooter and homes to the Flying Bison and Winged Lemur), various rooms (used as bedrooms and various other things like pai sho) and another room only accessable via Airbending. This room contains statues of the past incarnations of the Avatar.
Northern Air Temple
Before the war, the Northern Air Temple was the home to Airbenders (most probably male, as the Western and Eastern were only home to females) and apparantly the Flying Bison polo championship.
After the temple and it's inhabitants were destroyed, the Northern Air Temple was found by the Mechanist and his group of refugees. The Mechanist's son, Teo, was left disabled from the waist down in the flood that destroyed their village and killed Teo's mother, so the Mechanist modified the old Gliders to give his son a new life in the air.
The Mechanist modified the whole temple for his peoples need. The whole temple runs on hot air, and the hot air can sometimes be used to give the gliders an extra lift.
The Mechanist used the Airbending access only room (although the Mechanist must have found another way to enter) to create weapons for the Fire Nation. But with The Gaang's help, the Mechanist rebels against the Fire Nation, and refuse to make anymore weapons.
Eastern Air Temple
The Eastern Air Temple was home to the female Airbenders before the war, although Aang was most probably born there as he selected Appa as his pet there. Before the war, the monks of the Southern Air Temple were going to send Aang to the Eastern Air Temple to continue his training away from Gyatso.
Guru Pathik recently helped Aang unlock six of the seven chakras there recently (he refused to oven the seventh as he would have to let go of Katara), so it is thought he might be living there now.
The Eastern Air Temple consist of three buildings perched on top of three mountains.
Western Air Temple
The Western Air Temple was a home to just female Airbenders, but they were all killed when the Air Temples were destroyed by Fire Lord Sozin and his troops.
The Gaang currecntly reside at the Western Air Temple, resting after the invasion.
The Temple is built upside down on the under side of a mountain side cliff.
The Air Nomads usually would wear orange and yellow clothing. The male Nomads shave there heads and the older ones would grow beards and moustaches. Woman would shave the front part of their head.
If an Airbender graduates to become a master, they are given special arrow tatoos. Females have the arrow on the front of their shaven head, while the males have an arrow tatoo that reaches over their head, down their back and seperates into four other arrows down their arms and legs.
The Airbenders detached themselves from the business of the world and didn't take part in all the fuss.
For more information on Airbenders/Airbending, see the Benders page.