The terms aerodrome, airfield, and airstrip may also be used to refer to airports, and the terms heliport, seaplane base, and STOLport refer to airports dedicated exclusively to helicopters, seaplanes, or short take-off and landing aircraft.

In colloquial use, the terms airport and aerodrome are often interchanged. However, in general, the term airport may imply or confer a certain stature upon the aviation facility that an aerodrome may not have achieved. In some jurisdictions, airport is a legal term of art reserved exclusively for those aerodromes certified or licensed as airports by the relevant national aviation authority after meeting specified certification criteria or regulatory requirements.

That is to say, all airports are aerodromes, but not all aerodromes are airports. In jurisdictions where there is no legal distinction between aerodrome and airport, which term to use in the name of an aerodrome may be a commercial decision. In United States technical/legal usage, landing area is used instead of aerodrome, and airport means "a landing area used regularly by aircraft for receiving or discharging passengers or cargo" .

Smaller or less-developed airports, which represent the vast majority, often have a single runway shorter than 1,000 m (3,300 ft). Larger airports for airline flights generally have paved runways 2,000 m (6,600 ft) or longer. Many small airports have dirt, grass, or gravel runways, rather than asphalt or concrete. Skyline Airport in Inkom, Idaho has a runway that is only 122 m (400 ft) long.

In the United States, the minimum dimensions for dry, hard landing fields are defined by the FAR Landing And Takeoff Field Lengths. These include considerations for safety margins during landing and takeoff. Heavier aircraft require longer runways.

The longest public-use runway in the world is at Qamdo Bamda Airport in China. It has a length of 5,500 m (18,045 ft). The world's widest paved runway is at Ulyanovsk Vostochny Airport in Russia and is 105 m (344 ft) wide.

As of 2009, the CIA stated that there were approximately 44,000 "... airports or airfields recognizable from the air" around the world, including 15,095 in the US, the US having the most in the world.

Airport ownership and operation

Most of the world's airports are owned by local, regional, or national government bodies who then lease the airport to private corporations who oversee the airport's operation. For example, in the United Kingdom the state-owned British Airports Authority originally operated eight of the nation's major commercial airports – it was subsequently privatized in the late 1980s, and following its takeover by the Spanish Ferrovial consortium in 2006, has been further divested and downsized to operating just Heathrow now. Germany's Frankfurt Airport is managed by the quasi-private firm Fraport. While in India GMR Group operates, through joint ventures, Indira Gandhi International Airport and Rajiv Gandhi International Airport. Bengaluru International Airport and Chhatrapati Shivaji International Airport are controlled by GVK Group. The rest of India's airports are managed by the Airports Authority of India. In Pakistan nearly all civilian airports are owned and operated by the Pakistan Civil Aviation Authority except for Sialkot International Airport which has a distinctions of being the first privately owned public airport in Pakistan and South Asia.

In the United States commercial airports are generally operated directly by government entities or government-created airport authorities (also known as port authorities), such as the Los Angeles World Airports authority that oversees several airports in the Greater Los Angeles area, including Los Angeles International Airport.

In Canada, the federal authority, Transport Canada, divested itself of all but the remotest airports in 1999/2000. Now most airports in Canada are owned and operated by individual legal authorities or are municipally owned.

Many U.S. airports still lease part or all of their facilities to outside firms, who operate functions such as retail management and parking. In the U.S., all commercial airport runways are certified by the FAA under the Code of Federal Regulations Title 14 Part 139, "Certification of Commercial Service Airports" but maintained by the local airport under the regulatory authority of the FAA.

Despite the reluctance to privatize airports in the US (despite the FAA sponsoring a privatization program since 1996), the government-owned, contractor-operated (GOCO) arrangement is the standard for the operation of commercial airports in the rest of the world.

Landside and airside areas

Airports are divided into landside and airside areas. The landside area is open to the public, while access to the airside area is tightly controlled. The airside area includes all parts of the airport around the aircraft, and the parts of the buildings that are only accessible to passengers and staff. Passengers and staff must be checked by security before being permitted to enter the airside area. Conversely, passengers arriving from an international flight must pass through border control and customs to access the landside area, where they can exit the airport. Many major airports will issue a secure keycard called an airside pass to employees, as some roles require employees to frequently move back and forth between landside and airside as part of their duties.

A terminal is a building with passenger facilities. Small airports have one terminal. Large ones often have multiple terminals, though some large airports like Amsterdam Airport Schiphol still have one terminal. The terminal has a series of gates, which provide passengers with access to the plane.

The following facilities are essential for departing passengers:

• Check-in fac