Transport

Transport is the intentional movement of people, animals, and goods from one location to another.

This process is vital because it enables human trade. Trade is a key driver for the development of civilizations. To understand how the world moves, we can divide transport into three main areas: infrastructure, vehicles, and operations. Infrastructure includes fixed installations like roads, railways, and pipelines. Terminals, such as airports and seaports, serve as hubs for exchanging passengers and cargo.

They also provide essential spaces for maintenance and refueling.

A mode of transport is a specific solution using a certain vehicle, infrastructure, and operation.

Travelers often choose a mode based on cost, capability, and the specific route. Sometimes, a journey requires more than one mode of transport. This is known as inter-modal or multi-modal transport. Governments often regulate these systems through financing, legalities, and specific policies. Ownership can be public, private, or a partnership between the two. For example, a city might have government-owned urban transport alongside privately owned cars.

Human-powered transport relies on human muscle power. This includes activities like walking, running, and swimming. It is considered a sustainable form of transport. While humans can walk without much infrastructure, roads and sidewalks improve accessibility. This is especially true when using human-powered vehicles like bicycles or wheelchairs.

Technology has also created hybrid vehicles. Personal transporters are a 21st-century example of hybrid human-electric powered vehicles. Animal-powered transport is another historical method. Humans use working animals to ride, to act as pack animals, or to pull wheeled vehicles. This remains useful in rough terrain where automotive transport cannot reach.

Air transport offers incredible speed.

Fixed-wing aircraft, or airplanes, use air moving over their wings to generate lift. This is different from rotary-wing aircraft, which use moving lift surfaces to create lift. Aircraft require an airport for refueling and loading. Some aerostats, or lighter-than-air aircraft, use different principles. They gain lift by containing gas that is less dense than the atmosphere. This includes balloons and airships, such as blimps. These often use helium or heated air to stay aloft.

Air travel is the second fastest method of transport, following the rocket.

Commercial jets can reach speeds of up to 955 kilometres per hour. Single-engine aircraft are slower, reaching about 555 kilometres per hour. Aviation allows for the quick movement of people and limited cargo. However, it also involves high costs and high energy use. As of April 28, 2009, the WHO estimated that up to 500,000 people were on planes at any given time. Modern technology has also introduced unmanned aerial vehicles, known as drones. These can carry payloads for tasks like package delivery.

Land transport is divided into rail and road systems.

Rail transport uses wheeled vehicles running on tracks. These tracks consist of parallel steel rails anchored to ties made of timber, concrete, or steel. The distance between the rails is called the gauge. A locomotive provides the propulsion to haul unpowered cars, known as rolling stock.

Rail is often more energy efficient than road transport because it has less friction. High-speed rail can reach 350 km/h. In Shanghai, commercial maglev transport can reach 460 km/h. Freight has also shifted toward containerization since the 1980s.

Road transport provides high flexibility for users.

Drivers can change lanes, directions, and speeds according to their needs. This allows for efficient door-to-door service. However, road systems consume large amounts of land and can cause urban congestion. They are also a major source of noise and air pollution. As of 2015, there were 950 million passenger cars worldwide. This number is projected to reach 2.5 billion by 2050. While automobiles offer low capacity, buses provide a more efficient way to move many people.

Water transport involves moving across bodies of water using watercraft.

This includes boats, ships, and barges. A critical part of a watercraft is the hull, which provides buoyancy. In the 19th century, steam ships used boilers and external combustion engines. Today, most commercial ships use internal combustion engines fueled by bunker fuel. Some specialized vessels, like submarines, use nuclear marine propulsion. This uses heat from a nuclear reactor to generate steam. Other craft still rely on traditional methods like wind or oars.