Central business district

A central business district (CBD) is the commercial and business centre of a city. In larger cities, it is often synonymous with the city's "financial district". Geographically, it often coincides with the "city centre" or "downtown", but the two concepts are separate: many cities have a central business district located away from its commercial or cultural city centre or downtown. Both the CBD and the city centre or downtown may also coincide with the central activities district.

A city's CBD is usually typified by a concentration of retail and office buildings. The CBD usually has an urban density higher than the surrounding districts of the city, and is often the location of the tallest buildings in the city.

The CBD is often also the "city centre" or "downtown", but this is also often not the case. Midtown Manhattan is the largest central business district in New York City and in the Western Hemisphere; yet Lower Manhattan, commonly referred to as Downtown Manhattan, actually represents the second largest distinct CBD in New York City and is geographically situated south of Midtown. For example, London's "city centre" is usually regarded as encompassing the historic City of London and the medieval City of Westminster, whereas the City of London and the transformed Docklands area are regarded as its two CBDs. Mexico City also has a historic city centre, the colonial-era Centro Histórico, along with two CBDs: the mid-late 20th century Paseo de la Reforma - Polanco, and the new Santa Fe. In Taipei, Taiwan, the area around its main railway station is regarded as the historic city centre while the Xinyi Planned Area located to the east of the said railway station is the current CBD of Taipei, being both the financial district and the premier shopping area, and the location of Taipei 101, Taipei's tallest building.

La Défense

La Défense (French: [la de.fɑ̃s]) is a major business district of the Paris Metropolitan Area and of the Île-de-France region, located in the commune of Courbevoie, and parts of Puteaux and Nanterre, just west of the city of Paris.

La Défense is Europe's largest purpose-built business district with 560 hectares (5.6 million square metres) area, 72 glass and steel buildings of which 18 are completed skyscrapers, 180,000 daily workers, and 3.5 million square metres (37.7 million sq ft) of office space. Around its Grande Arche and esplanade ("le Parvis"), La Défense contains many of the Paris urban area's tallest high-rises.

The district is located at the westernmost extremity of the ten-kilometre-long Historical Axis of Paris, which starts at the Louvre in Central Paris, and continues along the Champs-Élysées, well beyond the Arc de Triomphe along the Avenue de la Grande Armée before culminating at La Défense. The district is centred in an orbital motorway straddling the Hauts-de-Seine département municipalities of Courbevoie, Nanterre and Puteaux. La Défense is primarily a business district, and hosts a population of 25,000 permanent residents and 45,000 students. La Défense is also visited by 8,000,000 tourists each year, and houses an open-air museum.

Milan

Milan (English /mᵻˈlæn/ or US /məˈlɑːn/;Lombard, Milanese variant: Milan [miˈlã]),Italian: Milano [miˈlaːno]), the second-most populous city in Italy, is the capital of Lombardy. The city proper has a population of about 1.3 million, while its urban area (the 5th-largest in the EU) comprises an estimated 5 million people (former Provinces of Milan and Monza-Brianza, with other Comuni included in the former Province of Varese). The enormous suburban sprawl that followed the post-war boom of the 1950s–1960s has resulted in a polycentric metropolitan area, known as Greater Milan, of 7 to 10 million people, stretching over the provinces of Milan, Bergamo, Como, Lecco, Lodi, Monza and Brianza, Pavia, Varese and Novara. The Milan metropolitan region is part of the so-called Blue Banana, the area of Europe with the highest population and industrial density. In terms of GDP, Milan has the third largest economy among EU cities (after London and Paris) and the largest among European non-capital cities.

New York

New York is a state in the Northeastern United States and is the United States' 27th-most extensive, fourth-most populous, and seventh-most densely populated state. New York is bordered by New Jersey and Pennsylvania to the south and Connecticut, Massachusetts, and Vermont to the east. The state has a maritime border in the Atlantic Ocean with Rhode Island, east of Long Island, as well as an international border with the Canadian provinces of Quebec to the north and Ontario to the west and north. The state of New York, with an estimated 19.8 million residents in 2015, is often referred to as New York State to distinguish it from New York City, the state's most populous city and its economic hub.

With an estimated population of nearly 8.5 million in 2014, New York City is the most populous city in the United States and the premier gateway for legal immigration to the United States. The New York City Metropolitan Area is one of the most populous urban agglomerations in the world. New York City is a global city, exerting a significant impact upon commerce, finance, media, art, fashion, research, technology, education, and entertainment, its fast pace defining the term New York minute. The home of the United Nations Headquarters, New York City is an important center for international diplomacy and has been described as the cultural and financial capital of the world, as well as the world's most economically powerful city. New York City makes up over 40% of the population of New York State. Two-thirds of the state's population lives in the New York City Metropolitan Area, and nearly 40% live on Long Island. Both the state and New York City were named for the 17th century Duke of York, future King James II of England. The next four most populous cities in the state are Buffalo, Rochester, Yonkers, and Syracuse, while the state capital is Albany.

North America

North America is a continent entirely within the Northern Hemisphere and almost all within the Western Hemisphere. It can also be considered a northern subcontinent of the Americas. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the west and south by the Pacific Ocean, and to the southeast by South America and the Caribbean Sea.

North America covers an area of about 24,709,000 square kilometers (9,540,000 square miles), about 16.5% of the earth's land area and about 4.8% of its total surface. North America is the third largest continent by area, following Asia and Africa, and the fourth by population after Asia, Africa, and Europe.

In 2013, its population was estimated at nearly 565 million people in 23 independent states, or about 7.5% of the world's population, if nearby islands (most notably the Caribbean) are included.

North America was reached by its first human populations during the last glacial period, via crossing the Bering land bridge. The so-called Paleo-Indian period is taken to have lasted until about 10,000 years ago (the beginning of the Archaic or Meso-Indian period). The Classic stage spans roughly the 6th to 13th centuries. The Pre-Columbian era ended with the arrival of European settlers during the Age of Discovery and the Early Modern period. Present-day cultural and ethnic patterns reflect different kind of interactions between European colonists, indigenous peoples, African slaves and their descendants. European influences are strongest in the northern parts of the continent while indigenous and African influences are relatively stronger in the south. Because of the history of colonialism, most North Americans speak English, Spanish or French and societies and states commonly reflect Western traditions.