The First Doctor is the name given to the first incarnation of the fictional character known as the Doctor seen on screen in the long-running BBC television science-fiction series Doctor Who.
The Second Doctor is the name given to the second incarnation of the fictional character known as the Doctor seen on screen in the long-running BBC television science-fiction series Doctor Who. He was portrayed by the actor Patrick Troughton.
The Third Doctor is the name given to the third incarnation of the fictional character known as the Doctor seen on screen in the long-running BBC television science-fiction series Doctor Who. He was portrayed by actor Jon Pertwee.
The Fourth Doctor is the name given to the fourth incarnation of the fictional character known as the Doctor seen on screen in the long-running BBC television science-fiction series Doctor Who.
The Fifth Doctor is the name given to the fifth incarnation of the fictional character known as the Doctor seen on screen in the long-running BBC television science-fiction series Doctor Who. He was portrayed by actor Peter Davison.
The Sixth Doctor is the name given to the sixth incarnation of the fictional character known as the Doctor, seen on screen in the long-running BBC television science-fiction series Doctor Who.
The Seventh Doctor is a fictional character, the seventh incarnation of the Doctor seen on screen in the long-running BBC television science-fiction series Doctor Who. He was portrayed by the actor Sylvester McCoy.