The Eleventh Doctor is an incarnation of the Doctor, the protagonist of the BBC science fiction television series Doctor Who.
Matt Smith plays this incarnation.
Within the series’ narrative, The Doctor is a centuries-old alien, a Time Lord from the planet Gallifrey, who travels in time and space in his TARDIS, frequently with companions. When the Doctor is critically injured, he can regenerate his body but in doing so gains a new physical appearance and with it, a distinct new personality.
Matt Smith portrays the eleventh such incarnation, a quick-tempered but compassionate man whose youthful appearance is at odds with his more discerning and world-weary temperament. The current companion to the 11th Doctor is Amy Pond who is played by Karen Gillan. Source – Wikipedia
I like the bit when someone says ‘It’s bigger on the inside
11th Doctor