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
Yellow Cab Company equally divided amongst Hertz, Parmelee and a small group of other investors. Hertz sold the Yellow Cab Manufacturing Company to General Motors in 1925. He sold his remaining interest in the Yellow Cab Company in 1929. Yellow Cab Co. (of Chicago) was bought by Morris Markin, who had established Checker Cab Manufacturing Company, with the Checker Taxi, a driver's cooperative. In 1929 he sold his remaining share of Yellow Cab to concentrate on car rental (later Hertz Rent-a-Car which incidentally still uses a yellow logo). The sale was prompted by the violence associated with the business that culminated in 1928