- 21s
- Stage 5 appearances, about 21 days apart. Candidates name the appearance stages after their gaps; TfL does not use the words. See appearances.
- 28s
- Stage 4 appearances, about 28 days apart.
- 56s
- Stage 3 appearances, about 56 days apart: the first stage of appearances.
- All London
- The full Knowledge, and the licence it leads to: a driver who can work anywhere in Greater London. Its badge is green.
- Appearance
- A one-to-one oral exam with a Knowledge examiner, up to 30 minutes for your first and 20 for every one after, in which you locate two points and call the route between them, four times.
- Blue Book
- TfL's list of the 320 runs that make up the All London Knowledge, in 20 lists of 16. Candidates learn the runs in its order. See all 320 runs.
- Calling a run
- Saying a route aloud, road by road and turn by turn, from the moment you leave the first point to where you set down at the second. It is what an examiner asks for.
- Call-over
- Practising with a partner: one sets a run or a point, the other calls it, and the first checks every turn.
- Charing Cross
- The centre of the Knowledge, at the statue of King Charles I. The All London Knowledge covers everything within six miles of it, about 113 square miles.
- Dumbbell
- A run learned as TfL describes it: the route in the middle, and the circle of streets and points at each end.
- Forward (F)
- In a called run, carrying straight on into the next road. Left and right are L and R.
- Green badge
- An All London taxi driver's badge, worn while working. See green or yellow badge.
- Leave by (L/by)
- The road you leave the first point by: how every called run begins.
- Points
- Places a passenger might ask for: hotels, hospitals, stations, theatres, clubs, embassies, courts, parks and more. You learn every one within a quarter of a mile of each end of each run. TfL publishes them in its Points List.
- Quarter mile
- The radius around each end of a run in which the All London Knowledge asks every street and point: 402 metres. The Suburban Knowledge uses half a mile.
- Run
- A route between two points in the Blue Book, learned as the shortest legal way between them, in both directions.
- Self-assessment
- Stage 1 for All London candidates: a test after the first 80 runs that you mark yourself, with an examiner present. No record of the score is kept.
- SERU
- Safety, Equality and Regulatory Understanding: an assessment on fares, equality and disability, safeguarding, safe driving, stopping and waiting and the licensing rules, needed for a taxi licence since 1 October 2025.
- Set down
- Where you stop to let the passenger out, and on which side of the road. Getting it wrong costs marks.
- Suburban
- The Knowledge for, and the licence to work in, one of nine outer London sectors. Its badge is yellow.
- Written exam
- Stage 2 for All London candidates: multiple choice, on routes and points, after all 320 runs. The pass mark is 60 out of 100.
- Yellow badge
- A Suburban taxi driver's badge.
The Knowledge, word by word
The Knowledge has its own language. Here are the words you will hear at a school, at an appearance and in the Blue Book.
Checked against TfL's documents on 3 October 2026.
Read next
The stages of the KnowledgeThe self-assessment, the written exam, the appearances at Stages 3 to 5, the final Stage 6 exam and the licence: what each one asks, how it is passed and how long you have.Knowledge appearances, and how they are markedWhat happens at a Knowledge appearance, how each run is marked, what an A, B, C and D are worth, how many points move you up a stage, and what four Ds mean.Green badge or yellow badge?The difference between an All London (green badge) and a Suburban (yellow badge) taxi licence, the nine suburban sectors, how the Suburban Knowledge differs and how to move up later.
Learn the Knowledge with TheLTK
Every run and point, a plan for each day, and your calls checked turn by turn.