The TARDIS

A TARDIS or TT Capsule was the main kind of space-time vehicle used by the Time Lords. "TARDIS" was an acronym Susan had "made up the name 'TARDIS' from the initials" of the full name, "Time And Relative Dimension In Space". (DW: An Unearthly Child). Susan Foreman (later Susan Campbell) was the grand daughter if the 1st incarnation of The Doctor.

In his first incarnation, the Doctor implied that he had built his TARDIS himself. (DW: The Chase) It was later revealed that he had stolen it, although this did not necessarily preclude the notion that he had somehow been responsible for its creation. (DW: The War Games, ST: The Exiles) Marnal was the Time Lord who previously owned the TARDIS. (EDA: The Gallifrey Chronicles)
The Doctor's TARDIS was referred to by the Time Lords as being a Type 40. By the time of the Doctor's fourth incarnation, all Type 40s had been officially decommissioned and replaced by newer, improved models. All models except the Doctor's had been accounted for. (DW: The Deadly Assassin)

The defining characteristic of the Doctor's TARDIS was that its chameleon circuit had broken after assuming the shape of a police box in 1963, London. Eventually, friends and enemies would be able to locate the TARDIS because it failed to change shape. The Daleks recognized the police box as the transport of their enemy (DW: Death to the Daleks), as would the Cybermen (DW: Earthshock) and the agent of the Black Guardian known as the Shadow. (DW: The Armageddon Factor) Captain Jack Harkness was on the look-out for "a version of" the police box throughout the 20th and early 21st centuries. (DW: Utopia)

Entry to the Doctor's TARDIS was effected by inserting a key into the lock, just as would be expected from a real police box. However, the locking mechanism was anything but ordinary. It did not respond to police-issued keys, and indeed would not even open when unauthorized persons used the Doctor's keys. The Brigadier was prevented from opening the TARDIS in the Doctor's absence, because of the metabolism detector on the lock. (DW: Spearhead from Space) Nevertheless, there were occasions on which strangers were able to successfully use the Doctor's key, perhaps suggesting either a flaw in the metabolism detector or a sentient choice on the part of the TARDIS. (DW: Doctor Who (1996), DW: The War Machines, DW: Blink)

Using the Architectural Configuration system, the Doctor was able to change and re-arrange the interior of his TARDIS with ease. (DW: Logopolis, Castrovalva, DWA: 2006 Doctor Who Annual) The Fifth Doctor also called this "change[ing] the desktop theme" (DW: Time Crash) There have been many variants of the Doctor's TARDIS main control room. They usually share common features such as a hexagonal control console, and a set of doors allowing access to the outside via the outer plasmic shell as well as to other rooms in the TARDIS and usually a scanner or some other means of observing the outside.

There are many rooms inside of the TARDIS such as a Library, Wardrobe, Bathrooms, Sleeping Quarters, a laboratory, other control rooms, and more!

As TARDISes were intelligent, the Doctor's TARDIS had also developed a personality. It had been called "sentimental" (DW: Doctor Who (1996)) and "stupid" (by K-9) (DW: The Invasion of Time). Though intelligent, it was generally unable to communicate in words with the Doctor, relying on other methods of communication. (DW: The Edge of Destruction)

The TARDIS has also displayed a prejudicial fear of the time-locked Jack Harkness, probably relating in some way to its time travelling abilities, as the Doctor admits that due to his time related senses he finds it harder to look at Jack now. (DW: Utopia)

When the Doctor was attacked by Es'Cartress, the TARDIS tried to help him in the Matrix, taking the forms of his companions and helping him regain him memories. (IDW: The Forgotten)

Although the Doctor was reluctant to believe it possible, his TARDIS seems to have such a strong affinity for the Doctor that it would open and shut its doors when he snapped his fingers. The Tenth Doctor tested this ability after being informed of it by River Song, and was able to do so. Later, the Eleventh Doctor uses this ability when he takes Amy on as a companion to show off. (DW: Forest of the Dead, The Eleventh Hour)

While the Doctor was away on an adventure the TARDIS hummed to itself. (NSA: The Doctor Trap)

The Doctor has shown great tenderness towards the TARDIS, referring to it as his "dear old friend" on one occasion (DW: The Deadly Assassin), and simply "dear" on another. (DW: The Eleventh Hour) He has most commonly referred to the TARDIS as "she or "her". Although this would seem to be a term of endearment (much like how Earth males refer to their cars as "she's"), certain spin-off media suggests that the TARDIS may actually be female. (ST: The Lying Old Witch in the Wardrobe)

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