There are two kinds of taxis in operation within London. The famous Black Cab and minicabs. The major difference between the two is that Black Cabs can pick you up from the side of the street whilst minicabs must be booked in advance (they are not supposed to pick you up from the side of the road)
Almost anyone can become a Minicab driver. All they usually require is the use of their own car which has at least 4 doors. In order to order a minicab you usually have to call them up in advance or walk to a minicab office and they will call the nearest cab for you.
The quality of the minicab versus the traditional black cab can vary a great deal. Black cab drivers have to pass a test which is so complicated that it can often take 2 years of study to pass. Black cab drivers usually know the streets of London by heart and often the best routes to take to get you to your destination on time. Minicabs driver’s vary a lot more and often these days you’ll see minicab drivers with a TomTom or other similar satellite navigation system in their car to help them find the route to your destination.
Black cabs tend to cost a lot more then minicabs and a computer inside of the cab charges you first for a minimum charge, then on both the distance travelled and the time the journey takes. So if your cab runs into traffic they’re still making money, even if you’re not going anywhere.
Minicabs tend to charge a fixed price and you should always ask the price before the start of the journey. Occasionally you’ll get a rouge driver that tries to up the fare and charge more then the original price, in such cases it’s important to inform the control room about the driver.