The Doctor Edit
The doctor, is part of the alien race known as the Time-Lords. The doctors real name is unknown but he is thought to be the last surviving time-lord because of the Time war between the daleks and the time lords. Time lords, including the doctor, have the ability to regenerate. This is when the time lords body is old or damaged the time lords cells start to change making said time lord into a completely new person. The Doctor stole a type 60s T.A.R.D.I.S (time and relative dimention in space) and flew away to explore. The other time lords that the doctor has met are The master, The Rani, Rassilon and sevrel others but they (most) have probably died.