|Type||Time Travel Device|
A TARDIS is a product of the advanced technology of the Time Lords, an extraterrestrial civilization to which the programme's central character, the Doctor belongs. A properly maintained and piloted TARDIS can transport its occupants to any point in time and any place in the universe. The interior of a TARDIS is much larger than its exterior, which can blend in with its surroundings using the ship's "chameleon circuit".
In the series, the Doctor pilots an unreliable, obsolete TT Type 40, Mark 3 TARDIS. Its chameleon circuit is faulty, leaving it locked in the shape of a 1960s-style London police box after a visit to London in 1963. The Doctor's TARDIS was for most of the franchise's history said to have been stolen from the Time Lords' home planet, Gallifrey, where it was old, decommissioned and derelict (and, in fact, in a museum). However, during the events of "The Doctor's Wife", (2011) the ship's consciousness briefly inhabits a humanoid body, and she reveals that far from being stolen, she left of her own free will. During this episode, she reveals that she actually considers herself to have "stolen" the Doctor rather than the other way around, although she does also refer to him as her "thief" in the same episode. In that episode she also calls herself "Sexy" (as a name) because of what the Doctor called her after her last upgrade.