If you haven't guessed by her outfit, Leela is a tribal girl. She is a member of the Sevateem tribe, a savage group of individuals who turn out to be the decendants of space travelers whose ship crashed on a stange and foreign planet. In tact, the tribe's name is nothing but a badly garbled version of the phrase "Survey Team." Unlike many of the Doctor's other companions, Leela wasn't invited to join the TARDIS crew. She just sort of barged in and stuck around with the Doctor, who was more than content at the time to journey on his own.
