The TARDIS (Time And Relative Dimension In Space) is a sentient time-traveling spaceship, used by The Doctor, to explore the universe. Doctor is a Time Lord, a space-and-time-traveling humanoid alien. The Doctor and TARDIS belongs to the British science-fiction television program produced by the BBC. The program was first aired in the year 1963.
The TARDIS is made by the Time Lords using their advanced technology. A TARDIS that is maintained properly can transport the people in it to any point in time (unless it is time locked) and space if properly piloted. In the series, Doctor Who stole a TARDIS that is obsolete, and hence unreliable. It often fails to get him where he wants to go but send him where he needs to be.
The TARDIS is dimensionally transcendental. It means, the interior of a TARDIS is much bigger on the inside (yes squee away). The machine has a feature known as the chameleon circuit, which when activated, will help it to blend in with its surroundings, so as to avoid detection by other people. He just like to keep it as a police box. The TARDIS provides its users with a lot of tools and abilities, including a telepathically based universal translation system and force field. TARDIS has a library, a swimming pool, a large boot room, and a plethora of other rooms.