The Tardis
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THE T.A.R.D.I.S.
A T.A.R.D.I.S. is a machine invented by the time lords used to travel & observe time & space.
The word 'T.A.R.D.I.S.' stands for 'time and relative dimensions in space' & is also known as a 'TT capsule.' There were two types of T.A.R.D.I.S. the military & exploratory. Military (armed T.A.R.D.I.S.) were more common than the doctor's exploratory type used for observing time & space. the name 'T.A.R.D.I.S.' was invented by the doctor's granddaughter susan. The doctors T.A.R.D.I.S. we see in the form of a 1940's police box but a usual, working T.A.R.D.I.S. had a chameleon circuit this circuit made the exterior of a T.A.R.D.I.S. blend in to the time it had materialized into. Generally making the T.A.R.D.I.S. bigger on the inside than on the outside than on the outside, but the doctor's stolen type 40 T.A.R.D.I.S. did not possess this function. There have been other machines similar to a T.A.R.D.I.S. such as the time cannon and captain jack's vortex manipulator all using similar technology to the T.A.R.D.I.S.
The only T.A.R.D.I.S.'S we have seen are the doctor's stolen type 40 T.A.R.D.I.S. the master's T.A.R.D.I.S. the monk's mark 4 T.A.R.D.I.S. & Iris Wildthyme's T.A.R.D.I.S. (files on these characters coming soon)
the T.A.R.D.I.S. is a strange time machine although we know quite alot about it some of the T.A.R.D.I.S. greatest secrets are yet to be revealed.