The Doctor's TARDIS control room
The Doctor's TARDIS contained a console room, also known as a control room, which varied in structure and size across iterations. This changing of TARDIS appearance was described by the Fifth Doctor as changing the "desktop theme" (TV: Time Crash). One at least two occasions, it was the Doctor's violent regeneration which caused their TARDIS to completely overhaul its internal dimensions, without aid of the Doctor. (TV: The Eleventh Hour, Twice Upon a Time).
According to River Song, a TARDIS usually had multiple console rooms (AUDIO: The Lifeboat and the Deathboat). Indeed, the Doctor's TARDIS was shown on multiple occasions to have a #Secondary console room. (TV: The Masque of Mandragora, PROSE: The Dying Days), although both the Fourth and Eighth Doctors claimed it was actually the original, with the Eighth Doctor claiming he used it ages ago when he wore a tricorn hat.