TARDIS

    The TARDIS (aka, Time and Relative Dimension in Space), is a time machine the Doctor uses to travel through time with his companion. A triumph of Time Lord temporal engineering, TARDISes are "dimensionally transcendental" which means that the interior and exterior exist in different dimensions and they can change both their external appearance and internal layout. When the Doctor decided to flee Gallifrey and roam the universe, he stole a TARDIS awaiting servicing for a variety of malfunctions and faults. He has never been able to fully repair it, making his travels often erratic and uncontrolled.