North America is a continent entirely within the Northern Hemisphere and almost all within the Western Hemisphere; it is also considered by some to be 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 approximately 40,000 to 17,000 years ago. 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 transatlantic migrations and 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.

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South America is a continent located in the western hemisphere, mostly in the southern hemisphere, with a relatively small portion in the northern hemisphere. It is also considered a subcontinent of the Americas, which is the model used in Latin languages speaking nations. The reference to South America instead of other regions (like Latin America or the Southern Cone) has relatively increased in the last decades, due to geopolitical dynamics (in particular, the rise of Brazil in the subcontinent).

It is bordered on the west by the Pacific Ocean and on the north and east by the Atlantic Ocean; North America and the Caribbean Sea lie to the northwest. It includes twelve sovereign states – Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay, and Venezuela – and two non-sovereign areas – French Guiana, a region of France, and the Falkland Islands, a British Overseas Territory (though disputed by Argentina). In addition to this, the ABC islands of the Kingdom of the Netherlands, Trinidad and Tobago, and Panama may also be considered part of South America.

South America has an area of 17,840,000 square kilometers (6,890,000 sq mi). Its population as of 2005 has been estimated at more than 371,090,000. South America ranks fourth in area (after Asia, Africa, and North America) and fifth in population (after Asia, Africa, Europe, and North America). Brazil is by far the most populous South American country, with more than half of the continent's population, followed by Colombia, Argentina, Venezuela and Peru. In recent decades Brazil has also concentrated half of the region's GDP and has become a first regional power.

Most of the population lives near the continent's western or eastern coasts while the interior and the far south are sparsely populated. The geography of western South America is dominated by the Andes mountains; in contrast, the eastern part contains both highland regions and large lowlands where rivers such as the Amazon, Orinoco, and Paraná flow. Most of the continent lies in the tropics.

The continent's cultural and ethnic outlook has its origin with the interaction of indigenous peoples with European conquerors and immigrants and, more locally, with African slaves. Given a long history of colonialism, the overwhelming majority of South Americans speak Portuguese or Spanish, and societies and states commonly reflect Western traditions.

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