Easter egg
An Easter Egg is an intentional hidden message or feature within a DVD, CD, video or computer program in which when found and triggered can give access to bonus features or shows something that is not mentioned in the main list of contents.
In 2007, an Easter Egg featuring the Doctor was discovered on 14 different DVD releases in Great Britain, leading to some interest among Internet users, including Larry Nightingale, due to the one-sided message's cryptic nature. It was later discovered that the message was recorded in 1969 and addressed to Sally Sparrow, as part of a time travel-related paradox caused by the interference of the Weeping Angels (the 14 DVDs represented Sally's complete collection of discs at that time). One of the Doctor's statements in the message, "The angels have the phone box", was made into a T-shirt design. (DW: Blink)
Behind the scenes
Some Doctor Who discs contain hidden features that are more or less easy to find. These features are usually so small and insignificant that they would not really be appropriate for inclusion on the main disc menu. However, disc producers sometimes like to sneak these little gems onto the disc in "hidden" places.
When the 2007 season was released to DVD, the Blink Easter Egg message was, appropriately, included in the set as an Easter Egg.
