North America is a continent in the Earth's northern hemisphere and (chiefly) western hemisphere. It is bordered on the north by the Arctic Ocean, on the east by the North Atlantic Ocean, on the southeast by the Caribbean Sea, and on the south and west by the North Pacific Ocean; South America lies to the southeast. It covers an area of about 24,490,000 square kilometers (9,450,000 sq mi), about 4.8% of the planet's surface or about 16.4% of its land area. As of October 2006, its population was estimated at over 514,600,000. It is the third-largest continent in area, following Asia and Africa, and is fourth in population after Asia, Africa, and Europe. North America and South America are collectively known as the Americas.

North and South America are popularly accepted as having been named after Italian explorer Amerigo Vespucci by the German cartographer Martin Waldseemüller. Vespucci was the first European to suggest that the Americas were not the East Indies, but a different landmass previously undiscovered by Europeans. Vespucci was the first to discover South America and the Amerique mountains of Central America, which connected his discoveries to those of Christopher Columbus. The etymology is further complicated by the need of cartographers to come up with a name that paralleled the feminine names of the other continents (e.g. Europa, Asia, Africa etc.). The convention is to use the surname for naming discoveries except in the case of royalty and so a derivation from "Amerigo Vespucci" may be problematic.

The second and less generally accepted theory is that the continents are named after an English merchant named Richard Amerike from Bristol, who is believed to have financed John Cabot's voyage of discovery from England to Newfoundland in 1497. A minutely explored belief that has been advanced is that America was named for a Spanish sailor bearing the ancient Visigothic name of 'Amairick'. Another is that the name is rooted in an Native American language.

The vast majority of North America is on the North American Plate. Parts of California and western Mexico form the partial edge of the Pacific Plate, with the two plates meeting along the San Andreas fault. The southern-most portion of the continent and much of the West Indies lie on the Caribbean Plate, while the Juan de Fuca and Cocos Plates border the North American Plate on its western frontier.

The continent can be divided into four great regions (each of which contains many sub-regions): the Great Plains stretching from the Gulf of Mexico to the Canadian Arctic; the geologically young, mountainous west, including the Rocky Mountains, the Great Basin, California and Alaska; the raised but relatively flat plateau of the Canadian Shield in the northeast; and the varied eastern region, which includes the Appalachian Mountains, the coastal plain along the Atlantic seaboard, and the Florida peninsula. Mexico, with its long plateaus and cordilleras, falls largely in the western region, although the eastern coastal plain does extend south along the Gulf.

The western mountains are split in the middle, into the main range of the Rockies and the coast ranges in California, Oregon, Washington, and British Columbia with the Great Basin—a lower area containing smaller ranges and low-lying deserts—in between. The highest peak is Denali in Alaska.

The United States Geographical Survey states that the geographic center of North America is "6 miles west of Balta, Pierce County, North Dakota" at approximately 48°10′N 100°10′W / 48.167, -100.167, approximately 15 miles (25 km) from Rugby, North Dakota. The USGS further states that “No marked or monumented point has been established by any government agency as the geographic center of either the 50 States, the conterminous United States, or the North American continent.” Nonetheless, there is a 15 foot (4.5 m) field stone obelisk in Rugby claiming to mark the center.