Hackney carriage which a taxi may operate and include regulating the taximeter (not compulsory until 1907), the maximum age of the taxi (not more than 15 years), advertisements and the turning circle of . As part of the Transported by Design programme of activities, in 15 October 2015, after two months of public voting, the black cab was elected by Londoners as their favourite transport design icon. In London, hackney-carriage drivers have to pass a test called The Knowledge to demonstrate that they have an intimate knowledge of the geography of London streets, important buildings, etc. Learning The Knowledge allows the driver
Illegal taxicab operation as "kabu kabu". In Hong Kong, illegal cabs are usually referred to as "white card", due to the different licence plate appearance between commercial and non-commercial vehicles. In Malaysia, illegal taxicabs are called "prebet sapu" (sweep privates). In Mexico, illegal taxicabs are called "taxi pirata" (pirate taxi). In Norway and Denmark, an illegal cab is called "pirattaxi" (pirate taxi). In Sweden, an illegal taxicab is called "svarttaxi" (black taxi), and is short for black market taxi. In Trinidad and Tobago, illegal taxis are referred to as ""PH" cars". This is because of the coding used on licence plates to distinguish