The Tenth Doctor is the tenth incarnation of the protagonist

Doctor (Doctor Who)

The Doctor is the central character in the long-running BBC television science-fiction series Doctor Who, and has also featured in two cinema feature films, a vast range of spin-off novels, audio dramas and comic strips connected to the series....

 of the long-running BBC

BBC

The British Broadcasting Corporation is a British public service broadcaster. Its headquarters is at Broadcasting House in the City of Westminster, London. It is the largest broadcaster in the world, with about 23,000 staff...

  television science-fiction

Science fiction on television

Science fiction first appeared on a television program during the Golden Age of Science Fiction. Special effects and other production techniques allow creators to present a living visual image of an imaginary world not limited by the constraints of reality; this makes television an excellent medium...

 series Doctor Who

Doctor Who

Doctor Who is a British science fiction television programme produced by the BBC. The programme depicts the adventures of a time-travelling humanoid alien known as the Doctor who explores the universe in a sentient time machine called the TARDIS that flies through time and space, whose exterior...

. He is played by David Tennant

David Tennant

David Tennant is a Scottish actor. In addition to his work in theatre, including a widely praised Hamlet, Tennant is best known for his role as the tenth incarnation of the Doctor in Doctor Who, along with the title role in the 2005 TV serial Casanova and as Barty Crouch, Jr...

, who appears in three series, as well as eight specials. As with previous incarnations of the Doctor, the character has also appeared in other Doctor Who multimedia

Doctor Who spin-offs

Doctor Who spin-offs refers to material created outside of, but related to, the long-running British science fiction television series Doctor Who....

.

In the series' narrative, the Doctor is a centuries-old Time Lord

Time Lord

The Time Lords are an ancient extraterrestrial race and civilization of humanoids in the British science fiction television series Doctor Who, of which the series' eponymous protagonist, the Doctor, is a member...

 alien from the planet Gallifrey

Gallifrey

Gallifrey is a fictional planet in the long-running British science fiction television series Doctor Who and is the homeworld of the Doctor and the Time Lords...

 who travels in time

Time travel in fiction

Time travel is a common theme in science fiction and is depicted in a variety of media. It simply means either going forward in time or backward, to experience the future, or the past.-Literature:...

 in his TARDIS

TARDIS

The TARDISGenerally, TARDIS is written in all upper case letters—this convention was popularised by the Target novelisations of the 1970s...

, frequently with companions

Companion (Doctor Who)

In the long-running BBC television science fiction programme Doctor Who and related works, the term "companion" refers to a character who travels with, and shares the adventures of the Doctor. In most Doctor Who stories, the primary companion acts as both deuteragonist and audience surrogate...

.