Info text
Info text (occasionally rendered info-text, also known as production information subtitles) is production information put onto a secondary subtitle track on Doctor Who DVDs. It is a feature virtually exclusive to the DVD releases of the 1963 version of the show.
The information varies on each release, and may include things like ratings figures, casting information, uncredited personnel who worked on a serial, or details about how a particular scene was filmed. Often, the info text concerns itself with what might have been: locations or actors the production team couldn't contract, other roles that the actors then onscreen turned down, and the like. Only rarely does the info text deal with continuity issues within the narrative itself.