Police box

A police box, used in the United Kingdom throughout the 20th century, is a public telephone kiosk or callbox for the use of members of the police, or for members of the public to contact the police. Unlike an ordinary callbox, its telephone was located behind a hinged door so it could be used from the outside, and the interior of the box was, in effect, a miniature police station for use by police officers to read and fill in reports, take meal breaks and even temporarily hold prisoners until the arrival of transport.

Police boxes predate the era of mobile telecommunications; now members of the British police carry two-way radios and/or mobile phones rather than relying on fixed kiosks. Most boxes are now disused or have been withdrawn from service.

The typical police box contained a telephone linked directly to the local police station, allowing patrolling officers to keep in contact with the station, reporting anything unusual or requesting help if necessary. A light on top of the box would flash to alert an officer that he/she was requested to contact the station. Members of the public could also use the phone to contact a police station in an emergency or, in the case of the Metropolitan Police, for assistance with any matter normally within the purview of the police.

Police boxes were usually blue, with the most notable exception being Glasgow, where they were red until the late 1960s. In addition to a telephone, they contained equipment such as an incident book, a fire extinguisher and a first aid kit. Today the image of the blue police box is widely associated with the science fiction television programme Doctor Who, in which the protagonist's time machine, a TARDIS, is in the shape of a 1960s British police box. In the context of a TARDIS, the image of the blue police box is a trademark of the BBC.

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