Mode of transport is a term used to distinguish between different ways of transportation or transporting people or goods. The different modes of transport are air, water, and land transport, which includes Rails or railways, road and off-road transport. Other modes also exist, including pipelines, cable transport, and space transport. Human-powered transport and animal-powered transport are sometimes regarded as their own mode, but never fall into the other categories. In general, transportation is used for moving of people, animals, and other goods from one place to another. The means of transport, on the other hand, refers to the (motorized) vehicles necessary for transport according to the chosen mode (car, airplane, ship, truck and rail). Each mode of transport has a fundamentally different technological solution, and some require a separate environment. Each mode has its own infrastructure, vehicles, and operations.
Animal-powered transport is the use of working animals for the transport of people and/or goods. Humans may use some of the animals directly, use them as pack animals for carrying goods, or harness them, alone or in teams, to pull sleds or wheeled vehicles.
A fixed-wing aircraft, typically airplane, is a heavier-than-air flying vehicle, in which the special geometry of the wings generates lift and then lifts the whole vehicle. Fixed-wing aircraft range from small trainers and recreational aircraft to large airliners and military cargo aircraft. For short distances or in places without runways, helicopters can be operable. (Other types of aircraft, like autogyros and airships, are not a significant portion of air transport.)
Air transport is the fastest method of transport, Commercial jets reach speeds of up to 955 kilometres per hour (593 mph) and a considerably higher ground speed if there is a jet stream tailwind, while piston-powered general aviation aircraft may reach up to 555 kilometres per hour (345 mph) or more. This celerity comes with higher cost and energy use, and aviation’s impacts to the environment and particularly the global climate require consideration when comparing modes of transportation. The Intergovernmental Panel on Climate Change (IPCC) estimates a commercial jet’s flight to have some 2-4 times the effect on the climate than if the same CO2 emissions were made at ground level, because of different atmospheric chemistry and radiative forcing effects at the higher altitude. U.S. airlines alone burned about 16.2 billion gallons of fuel during the twelve months between October 2013 and September 2014. WHO estimates that globally as many as 500,000 people at a time are on planes. The global trend has been for increasing numbers of people to travel by air, and individually to do so with increasing frequency and over longer distances, a dilemma that has the attention of climate scientists and other researchers, the press, and the World Wide Web. The issue of impacts from frequent travel, particularly by air because of the long distances that are easily covered in one or a few days, is