Underground Masker presents the Tube Challenge Glossary. Essential for Tube Challengers, inexperienced or veteran.

CCTV n. Counter-Challenge Tube Vision. A system of cameras used to pinpoint the location of Tube Challengers within a station, to aid deployment of "harassment" police officers and to ensure that train doors close before the Challengers reach them.

Cross-Platform Interchange n. Lines A and B converge in the same direction at a station, so passengers travelling in one geographic direction may pass directly from the platform of line A to that of line B.

Example: Oxford Circus, Bakerloo & Victoria lines.
Example: Finsbury Park, Victoria & Piccadilly lines.

Detrain v. 1. The act of all passengers on a train being asked to leave it.
2. The act of a Tube Challenger leaving a train.

Doors n. Parts of a train designed to get in the way of Tube Challengers and generally pose a nuisance. Doors can cause all manner of delays if they fail to close properly. Doors are usually closed just before the arrival of the Tube Challengers to the train. Works in close partnership with CCTV.

Platform n. Part of a station where Tube Challengers are advised to board trains. Boarding a train anywhere else is generally frowned upon.

PTSD n. 1. Post Tube-challenge Stress Disorder: an affliction causing Challengers to atempt to run between trains during normal everyday life, and become more upset than usual when a train is late or a bad connection made.
2. Post Tube-challenge Shower Detox.

Signal n. A set of coloured lights that tell drivers how much of a delay they should apply to the journey. Can be green (5 minutes' delay), yellow (10 minutes) or red (up to an hour).

Station Assistant n. A member of staff, supposed to be of some help to passengers and Tube Challengers. Says "mind the doors" and variants thereof.

Ticket n. A small rectangle of card, or Oyster-borne electronic concept or entity, enabling Tube Challengers to pass through ticket barriers with varying degrees of success.

Ticket Barrier n. A machine designed to eat paper tickets and prevent Oyster users from gaining access to the trains.

Train n. A vehicle, seldom seen on railways, of little interest to Tube Challengers or passengers alike.

Train Operator n. Synonym: Driver. Corporate syllable increase syndrome has increased the number of syllables required to describe this member of staff from two to five.