Earth has seven main pieces of land, called continents. The seven continents are Asia, Africa, North America, South America, Antarctica, Europe, and Australia/Oceania. They are listed here in order of size. Asia is the biggest. Australia/Oceania is the smallest.


Usually, nearby islands are also part of a continent. For example, Japan is part of Asia. Greenland and all the islands in the Caribbean Sea are usually considered part of North America. Only a very few islands are not part of any continent.

Europe and Asia are not really separate pieces of land. They are both part of a single, huge piece of land called Eurasia. Still, they are usually thought of as two separate continents because their societies developed separately.

Three Main Layers Make Up Earth

Earth is made up of three main layers. The core is in the center. The mantle wraps around the core. The outer crust is like Earth's skin.

The crust and the top part of the mantle form a hard, stiff shell. This shell covers Earth. It is broken up into huge parts called tectonic plates. These plates slide around on the mantle. For hundreds of millions of years, they have been slowly sliding around the surface of Earth. They are still sliding today. Scientists believe their constant sliding formed the continents.

The continents first began to form nearly four billion years ago. At that time, a huge ocean covered Earth. Then pieces of land began to appear. They built up along the edges of tectonic plates. They were made of rock that rose up when plates crashed into each other.

Some of this rock formed into small islands. When plates carrying these islands crashed into each other, the separate islands sometimes joined together. Over time, these islands grew larger and larger. They became the first continents.

When There Was a Single, Huge Continent

The early continents were scattered chunks of land. These chunks slowly moved toward each other. In time, they formed into a single, huge continent. Scientists call this supercontinent Pangaea.


About 200 million years ago, Pangaea began to break apart. The separate pieces then slowly moved away from each other. They were the beginnings of the continents we know today.


One giant piece that split off from Pangaea later became Europe, Asia, and North America. Antarctica and Australia also broke away. At the time, they were still joined together. The small piece of land that would become India broke away too. For millions of years it moved north as a large island. It finally ran into Asia. Slowly, the different landmasses moved to their present places.


The positions of the continents are always changing. North America and Europe are moving away from each other. They drift apart by about 2.5 centimeters (one inch) a year. The continents are also continuing to break apart. In time, part of California will likely separate from North America. It will become an island.


The Crashing of Tectonic Plates Produced Mountains

The surface of the continents has changed many times. Great mountains have risen. Then, they have been worn away. Ocean waters have flooded huge areas and then slowly dried up. Huge ice sheets have come and gone. They shaped the land as they advanced and then melted away.


Mountains continue to form on every continent. They often form through the crashing together of two tectonic plates. The force of the crash creates raised wrinkles in the crust. These "wrinkles" are what we call mountains. 


North America

North America is the third-largest continent. It stretches from the Aleutian Islands in the northwest to the Isthmus of Panama in the south.

The western part of the continent is full of young mountains. The Rockies are one example. They are North America's largest mountain chain. The East Coast has older mountain chains.

North America has a bigger range of climates than any other continent. Its Arctic regions are very cold. Other parts of the continent are very warm. For example, there are tropical jungles in the southern part of North America. The most southern part of North America is called Central America.


Some people think the United States and Canada are the only countries in North America. This is wrong. Mexico, Belize, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, and Panama are all in North America too. Greenland is also geographically part of North America, even though Denmark partly controls it.


South America

South America is the fourth-largest continent. It stretches from the Caribbean Sea to the Antarctic Circle.

The Andes is the longest mountain range on any continent. It runs the whole length of South America.

The Amazon River flows through northern South America. It is the largest river in the world. The Amazon runs through the world's largest tropical rain forest. This rain forest is home to thousands of kinds of plants and animals. Many are found nowhere else in the world.

There are 12 countries in South America.

Europe

Europe is the sixth-largest continent. It is only slightly larger than Canada. Yet, its population is more than twice that of South America. Europe has more than 40 countries.

The Ural Mountains separate Europe from Asia. Two nations are in both continents. These are Russia and Kazakhstan.

Europe's most famous mountain chain is the Alps. It stretches across eight countries.

Africa

Africa is the second-largest continent. It is more than three times bigger than the United States. From north to south, Africa stretches about 8,000 kilometers (5,000 miles).

The Sahara covers much of North Africa. It is the world's largest hot desert. The world's longest river, the Nile, is also in Africa. It flows more than 6,560 kilometers (4,100 miles).

The middle of Africa is full of flat, grassy plains. This region is home to many well-known kinds of animals. Among them are lions, giraffes, and elephants.

Africa also has large mountains. One example is Mount Kilimanjaro, in the country of Tanzania. Its peak is covered by snow all year long.

Africa is slowly splitting in two. In time, land containing four African countries will break off from the rest of the continent. Those countries are Eritrea, Ethiopia, Djibouti, and Somalia.

Africa is home to 56 countries.

Asia


Asia is the largest continent. It stretches from the eastern Mediterranean Sea to the western Pacific Ocean. Six-tenths of Earth's population lives in Asia. More than a third of the world's people live in China and India alone.


Asia has many different climate regions. The Siberian Arctic is very cold. Indonesia is tropical. China's Gobi Desert is dry year-round.


Asia has more mountains than any other continent. More than 50 of the tallest mountains in the world are in Asia. Mount Everest is the highest point on Earth. It is more than 8,700 meters (29,000 feet) high. Mount Everest is in both Nepal and China.


There are more than 40 countries in Asia.


Australia/Oceania


Thousands of islands sit in the Pacific Ocean. Many of them are part of a region called Oceania.


Oceania includes the continent of Australia. It also includes a microcontinent called Zealandia, which includes the country of New Zealand. Much of Zealandia is formed by rocks that are underwater, with only New Zealand poking through the ocean surface.


The other large land area in Oceania is the island of New Guinea. It contains the country of Papua New Guinea.


Oceania also includes three areas made up of only islands. These areas are Melanesia, Micronesia, and Polynesia. Hawai'i is in Polynesia.


Australia/Oceania is the smallest continent, and also the flattest. Australia/Oceania has the second-smallest population of any continent. Fewer than 40 million people live there. Most live in coastal cities. 


Australia/Oceania is full of unusual animals. Among them are the kangaroo, the koala, the platypus, and the Tasmanian devil.


Antarctica


Antarctica is the iciest place on Earth. It is larger than Europe or Australia, but has no full-time population. The only people there are visiting scientists.


Antarctica is unbelievably cold. Temperatures drop to lower than 73 degrees Celsius (100 degrees Farenheit) below zero. The continent is almost completely covered with ice. This ice covering can be up to 3.2 kilometers (two miles) deep. 


Antarctica does not have any countries. 

 

Continent
This map beautifully illustrates the continent of Australia.
Noun

the art and science of cultivating land for growing crops (farming) or raising livestock (ranching).

ancient
Adjective

very old.

Antarctic Circle
Noun

line of latitude at 66.5 degrees south that encircles the continent of Antarctica.

arc
Noun

part of the outline of a circle.

Noun

layers of gases surrounding a planet or other celestial body.

barren
Adjective

unproductive.

Noun

a dip or depression in the surface of the land or ocean floor.

Noun

body of water partially surrounded by land, usually with a wide mouth to a larger body of water.

Noun

narrow strip of land that lies along a body of water.

blanket
Verb

to cover entirely.

Noun

deep, narrow valley with steep sides.

cargo
Noun

goods carried by a ship, plane, or other vehicle.

cattle
Noun

cows and oxen.

Central America
Noun

region that connects North America and South America, including the Isthmus of Panama.

Noun

complex way of life that developed as humans began to develop urban settlements.

climate
Noun

all weather conditions for a given location over a period of time.

coastal range
Noun

recently formed mountains found near the coast of continents, especially the western coasts of the Americas.

coastline
Noun

outer boundary of a shore.

colonize
Verb

to establish control of a foreign land and culture.

communication
Noun

sharing of information and ideas.

complex
Adjective

complicated.

conquest
Noun

victory.

Noun

one of the seven main land masses on Earth.

continental crust
Noun

thick layer of Earth that sits beneath continents.

Noun

part of a continent that extends underwater to the deep-ocean floor.

Noun

tiny ocean animal, some of which secrete calcium carbonate to form reefs.

coral reef
Noun

rocky ocean features made up of millions of coral skeletons.

Noun

the extremely hot center of Earth, another planet, or a star.

craton
Noun

old, stable part of continental crust, made up of shields and platforms.

Noun

rocky outermost layer of Earth or other planet.

crustacean
Noun

type of animal (an arthropod) with a hard shell and segmented body that usually lives in the water.

Noun

learned behavior of people, including their languages, belief systems, social structures, institutions, and material goods.

debris
Noun

remains of something broken or destroyed; waste, or garbage.

Noun

destruction or removal of forests and their undergrowth.

descend
Verb

to go from a higher to a lower place.

Noun

area of land that receives no more than 25 centimeters (10 inches) of precipitation a year.

development
Noun

construction or preparation of land for housing, industry, or agriculture.

distinct
Adjective

unique or identifiable.

dominate
Verb

to overpower or control.

drastic
Adjective

severe or extreme.

dust
Noun

microscopic particles of rocks or minerals drifting in space. Also called cosmic dust or space dust.

economic
Adjective

having to do with money.

Noun

community and interactions of living and nonliving things in an area.

Noun

height above or below sea level.

enormous
Adjective

very large.

Noun

imaginary line around the Earth, another planet, or star running east-west, 0 degrees latitude.

Noun

act in which earth is worn away, often by water, wind, or ice.

Eurasia
Noun

landmass including the continents of Europe and Asia.

evaporate
Verb

to change from a liquid to a gas or vapor.

evolution
Noun

change in heritable traits of a population over time.

exploration
Noun

study and investigation of unknown places, concepts, or issues.

explorer
Noun

person who studies unknown areas.

extensive
Adjective

very large.

farmland
Noun

area used for agriculture.

fertile
Adjective

able to produce crops or sustain agriculture.

Noun

region extending from the eastern Mediterranean coast through Southwest Asia to the Persian Gulf.

Noun

overflow of a body of water onto land.

Noun

material, usually of plant or animal origin, that living organisms use to obtain nutrients.

fragile
Noun

delicate or easily broken.

frequent
Adjective

often.

freshwater
Noun

water that is not salty.

frigid
Adjective

very cold.

fuse
Verb

to combine or meld together.

gas
Noun

state of matter with no fixed shape that will fill any container uniformly. Gas molecules are in constant, random motion.

geographer
Noun

person who studies places and the relationships between people and their environments.

geologic
Adjective

having to do with the physical formations of the Earth.

geologist
Noun

person who studies the physical formations of the Earth.

geology
Noun

study of the physical history of the Earth, its composition, its structure, and the processes that form and change it.

Noun

natural hot spring that sometimes erupts with water or steam.

giant sequoia
Noun

largest species of tree on Earth.

glacial period
Noun

time of long-term lowering of temperatures on Earth. Also known as an ice age.

Noun

mass of ice that moves slowly over land.

Noun

harvested seed of such grasses as wheat, oats, and rice.

gravity
Noun

physical force by which objects attract, or pull toward, each other.

grazing animal
Noun

animal that feeds on grasses, trees, and shrubs.

Great Lakes
Noun

largest freshwater bodies in the world, located in the United States and Canada. Lake Huron, Lake Ontario, Lake Michigan, Lake Erie, and Lake Superior make up the Great Lakes.

Great Plains
Noun

grassland region of North America, between the Rocky Mountains and the Mississippi River.

headwater
Noun

source of a river.

hominid
Noun

biological family of primates, including humans, chimpanzees, gorillas, and orangutans, and their ancestors.

Horn of Africa
Noun

large peninsula in northeast Africa, including the countries of Somalia, Djibouti, Eritrea, and Ethiopia. Also called the Somali Peninsula.

ice age
Noun

long period of cold climate where glaciers cover large parts of the Earth. The last ice age peaked about 20,000 years ago. Also called glacial age.

ice core
Noun

sample of ice taken to demonstrate changes in climate over many years.

Noun

thick layer of glacial ice that covers a large area of land.

Noun

rock formed by the cooling of magma or lava.

Indian subcontinent
Noun

landmass in south-central Asia carried by the Indian tectonic plate, including the peninsula of India.

indicate
Verb

to display or show.

Adjective

characteristic to or of a specific place.

industry
Noun

activity that produces goods and services.

iron
Noun

chemical element with the symbol Fe.

Noun

body of land surrounded by water.

isolate
Verb

to set one thing or organism apart from others.

Noun

narrow strip of land connecting two larger land masses.

jungle
Noun

tropical ecosystem filled with trees and underbrush.

laboratory
Noun

place where scientific experiments are performed. Also called a lab.

Noun

specific natural feature on the Earth's surface.

Noun

the geographic features of a region.

lava
Noun

molten rock, or magma, that erupts from volcanoes or fissures in the Earth's surface.

legacy
Noun

material, ideas, or history passed down or communicated by a person or community from the past.

linguistic
Adjective

having to do with language or speech.

Noun

molten, or partially melted, rock beneath the Earth's surface.

Noun

middle layer of the Earth, made of mostly solid rock.

medicine
Noun

substance used for treating illness or disease.

metal
Noun

category of elements that are usually solid and shiny at room temperature.

Noun

type of rock that has crashed into Earth from outside the atmosphere.

Noun

study of weather and atmosphere.

microcontinent
Noun

a type of large continental island.

Noun

clouds at ground-level, but with greater visibility than fog.

molten
Adjective

solid material turned to liquid by heat.

Noun

seasonal change in the direction of the prevailing winds of a region. Monsoon usually refers to the winds of the Indian Ocean and South Asia, which often bring heavy rains.

mountain
Noun

landmass that forms as tectonic plates interact with each other.

mountain range
Noun

series or chain of mountains that are close together.

Noun

art and science of determining an object's position, course, and distance traveled.

Nubian Plate
Noun

tectonic plate currently being formed in western Africa as the African Plate splits in two.

Noun

large body of salt water that covers most of the Earth.

Oceania
Noun

region including island groups in the South Pacific.

oceanic crust
Noun

thin layer of the Earth that sits beneath ocean basins.

orogeny
Noun

the way mountains are formed.

Outback
Noun

remote, sparsely populated interior region of Australia.

pack ice
Noun

large area of drift ice, or ice not attached to a shoreline.

Pampas
Noun

flat grasslands of South America.

Pangaea
Noun

supercontinent of all the Earth's landmass that existed about 250 million years ago.

Noun

piece of land jutting into a body of water.

permanent
Adjective

constant or lasting forever.

Noun

flat, smooth area at a low elevation.

Noun

large region that is higher than the surrounding area and relatively flat.

Noun

movement and interaction of the Earth's plates.

platform
Noun

ancient rocks that formed as part of continental crust, now overlain with sediment and sedimentary rock, located in the interior of continents.

polar
Adjective

having to do with the North and/or South Pole.

Polynesia
Noun

island group in the Pacific Ocean between New Zealand, Hawaii, and Easter Island.

precious
Adjective

very valuable.

primitive
Adjective

simple or crude.

Noun

area of tall, mostly evergreen trees and a high amount of rainfall.

Noun

areas of fast-flowing water in a river or stream that is making a slight descent.

Noun

any area on Earth with one or more common characteristics. Regions are the basic units of geography.

remnant
Noun

something that is left over.

remote
Adjective

distant or far away.

research
Noun

scientific observations and investigation into a subject, usually following the scientific method: observation, hypothesis, prediction, experimentation, analysis, and conclusion.

research station
Noun

structure or structures built for scientific study of the surrounding region, possibly including residential and lab facilities.

Noun

depression in the ground caused by the Earth's crust spreading apart.

rigid
Adjective

stiff.

river system
Noun

tributaries, mouth, source, delta, and flood plain of a river.

savanna
Noun

type of tropical grassland with scattered trees.

Noun

base level for measuring elevations. Sea level is determined by measurements taken over a 19-year cycle.

Noun

solid material transported and deposited by water, ice, and wind.

Noun

rock formed from fragments of other rocks or the remains of plants or animals.

shield
Noun

ancient rocks that formed as part of continental crust and are located in the interior of continents.

Siberia
Noun

region of land stretching across Russia from the Ural Mountains to the Pacific Ocean.

snow
Noun

precipitation made of ice crystals.

snowmelt
Noun

water supplied by snow.

soil
Noun

top layer of the Earth's surface where plants can grow.

Somali plate
Noun

tectonic plate currently being formed in eastern Africa as the African plate splits in two.

sparse
Adjective

scattered and few in number.

stable
Adjective

steady and reliable.

straddle
Verb

to be on both sides of an issue, area, or object.

subduct
Verb

to pull downward or beneath something.

subduction
Noun

process of one tectonic plate melting, sliding, or falling beneath another.

subduction zone
Noun

area where one tectonic plate slides under another.

summit
Verb

to reach the highest point of a mountain.

supercontinent
Noun

ancient, giant landmass that split apart to form all the continents we know today.

tectonic plate
Noun

massive slab of solid rock made up of Earth's lithosphere (crust and upper mantle). Also called lithospheric plate.

terrestrial
Adjective

having to do with the Earth or dry land.

theorize
Verb

to formulate and propose a group of ideas to explain a scientific question.

Noun

rise and fall of the ocean's waters, caused by the gravitational pull of the moon and sun.

Tierra del Fuego
Noun

group of islands at the southern tip of South America.

tourism
Noun

the industry (including food, hotels, and entertainment) of traveling for pleasure.

trade
Noun

buying, selling, or exchanging of goods and services.

tropical
Adjective

existing in the tropics, the latitudes between the Tropic of Cancer in the north and the Tropic of Capricorn in the south.

unique
Adjective

one of a kind.

valley
Noun

depression in the Earth between hills.

vast
Adjective

huge and spread out.

vegetation
Noun

all the plant life of a specific place.

volcanic island
Noun

land formed by a volcano rising from the ocean floor.

Noun

an opening in the Earth's crust, through which lava, ash, and gases erupt, and also the cone built by eruptions.

Noun

flow of water descending steeply over a cliff. Also called a cascade.

Noun

the breaking down or dissolving of the Earth's surface rocks and minerals.

wheat
Noun

most widely grown cereal in the world.