Aes Sedai. Old Tongue for “Servant of All.” It is a society of those who wield the One Power, composed solely of women since the Breaking, when all men with the ability to channel went mad from the taint placed on saidin by the Dark One. The Aes Sedai divide themselves into seven groups, called Ajahs. Each Ajah has its own specialty: the Blue Ajah focused on causes; the Brown Ajah on scholarship; the Green Ajah on battle; the Gray Ajah on mediation; the Red Ajah on dealing with male channelers; the White Ajah on logic; and the Yellow Ajah on Healing.
There is a secret, eighth Ajah, whose existence is debated widely: the Black Ajah, who serves the Shadow.
The Aes Sedai are homed in the White Tower and are led by the Amyrlin Seat; the term was used both for the woman who led and for her throne. She is formally styled “The Watcher of the Seals, the Flame of Tar Valon, the Amyrlin Seat.” The Amyrlin Seat is chosen by the Hall of the Tower, and she is considered to be of All Ajahs and of None. The Hall of the Tower acts as the legislature; it consists of three representatives, called Sitters, from each Ajah.