Public transport is the most significant form of motor transport on Earth. Whilst in the Western World private cars rule, in meager countries (which symbolize the greater part of human population) most people cannot pay for a private car (or in dense urban areas the cost for parking), so walking, (motor) cycling or public transport are frequently the only options, with only the latter being viable for better distances. This frequently takes the form of mini-buses (jitneys) that might go after fixed routes but are typically flexible, including the option of taxi-style door-to-door transportation.
Public transport could be faster than other modes of journey where a separate transportation is used and thus much higher speeds are probable than are acceptable on roads. Prime examples are in cities where road congestion can be avoided (metro), and for long chilliness travel (trains). On roads this is also likely if the public transportation has its own part lanes. However, in fact the lanes are frequently shared, in which case public transport on roads is usually slower due to the (frequent) stops and changeovers. Additionally, public transport system might be weakly developed and thus can take up to two or might even three times longer than an equivalent trip in a private vehicle.