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The World

By Prof. Raju Vatsavayi

The planet

NameEarth — the third planet from the Sun and the only one known to hold life
AgeAbout 4.54 billion years
Surface area510.1 million km² (196.9 million sq mi)
Land area148.9 million km² (57.5 million sq mi) — 29.2% of the surface
Water area361.1 million km² (139.4 million sq mi) — 70.8% of the surface
Equatorial circumference40,075 km (24,901 mi)
Mean diameter12,742 km (7,918 mi); the Earth bulges at the equator, so the summit of Chimborazo in Ecuador, not Everest, is the point farthest from the planet’s center
MassAbout 5.97 × 10²⁴ kg
Distance from the SunAbout 149.6 million km (93.0 million mi) — one astronomical unit
Year365.256 days — hence a leap day every four years
Day23 hours 56 minutes 4 seconds of rotation; 24 hours from noon to noon
Axial tilt23.44° — the cause of the seasons
The MoonOne natural satellite, about 384,400 km (238,900 mi) away; first reached by humans on July 20, 1969
Continents7 — Asia, Africa, North America, South America, Antarctica, Europe, Australia (Oceania)
Oceans5 — Pacific, Atlantic, Indian, Southern, Arctic
Highest pointMount Everest, 8,848.86 m (29,032 ft), Nepal–China — fixed by the joint China–Nepal survey of 2020
Lowest point on landThe shore of the Dead Sea, Israel–Jordan, about 430 m (1,410 ft) below sea level and falling about a meter a year
Deepest pointThe Challenger Deep in the Mariana Trench, Pacific Ocean, about 10,935 m (35,876 ft); surveys give figures from 10,911 to 10,994 m

Quick facts

World populationAbout 8.3 billion (UN, 2026); it passed 8 billion on November 15, 2022
Countries193 United Nations member states and 2 observer states (the Holy See and Palestine) — the 195 most references count
Most populous countryIndia, about 1.46 billion (UN, 2025–26); China second at about 1.41 billion; the United States third at about 347 million
Least populous countryVatican City — a population in the hundreds
Largest country by areaRussia, about 17.1 million km² (6.6 million sq mi)
Smallest countryVatican City, 0.44 km² (0.17 sq mi)
Largest cityTokyo, Japan — about 37 million in the urban agglomeration (UN); Delhi is second and projected to overtake it
Most spoken languageEnglish, about 1.5 billion speakers including second-language speakers; Mandarin Chinese has the most native speakers, about 940 million
Largest religionChristianity, about 2.4 billion adherents — some 31% of people; Islam second, about 2 billion and growing fastest
World economyAbout US$118 trillion in 2025 (IMF, April 2026)
Largest economyUnited States, about US$30.8 trillion (2025) — 26% of the world total
Median ageAbout 31 years (2026); Africa is the youngest continent, with a median near 19, Japan and much of Europe the oldest
Life expectancy73.3 years at birth (2024, UN)
Urban shareAbout 58% of people live in cities (2026), up from 30% in 1950
Adult literacyAbout 87% of adults worldwide (UNESCO)
Internet usersAbout 5.5 billion — roughly two-thirds of humanity (ITU, 2024–25)
United NationsFounded October 24, 1945; headquarters in New York; six official languages — Arabic, Chinese, English, French, Russian, Spanish
Time zonesFrom UTC−12 to UTC+14 — 26 hours between the earliest and latest clocks; France has the most zones of any country, 12, through its overseas territories

Flags & world bodies

National flagsEvery UN member state and the observers fly a national flag; the oldest continuously used national flag is Denmark’s Dannebrog, dated by tradition to 1219, and Nepal’s is the only one that is not a rectangle.World Flags
Flag of the United NationsA world map in the azimuthal equidistant projection centered on the North Pole, within olive branches, in white on UN blue — adopted December 7, 1946
Olympic ringsFive interlaced rings on white, designed by Pierre de Coubertin in 1913 — the continents united; first flown at the 1920 Antwerp Games
The Red CrossA red cross on white — the Swiss flag reversed — adopted by the 1864 Geneva Convention; the Red Crescent joined it in 1876
UN Security CouncilFive permanent members with a veto — China, France, Russia, the United Kingdom, the United States — and ten elected for two-year terms
UN Secretary-GeneralThe organization’s chief officer, appointed for five-year terms by the General Assembly on the Council’s recommendation
Largest regional blocThe African Union — 55 member states
Largest economic blocThe European Union — 27 member states and a single market of about 450 million people
G20Nineteen countries plus the European Union and, since 2023, the African Union — about 85% of world GDP
Newest UN memberSouth Sudan, admitted July 14, 2011, five days after independence

Land & sea

Largest continentAsia, about 44.6 million km² (17.2 million sq mi) and about 60% of the world’s people
Smallest continentAustralia (Oceania), about 8.6 million km² (3.3 million sq mi) with its islands
Largest oceanPacific, 165.25 million km² (63.8 million sq mi) — larger than all the land on Earth put together; also the deepest, averaging about 4,280 m
Smallest oceanArctic, about 14 million km² (5.4 million sq mi)
Largest seaThe Philippine Sea, about 5 million km² (1.9 million sq mi); the Coral and Arabian seas follow
Longest riverNile, about 6,650 km (4,130 mi) by the traditional count; the Amazon, 6,400 km (3,980 mi) or more, is claimed longer by some measurements and carries the greatest flow of any river
Largest river by flowAmazon — about a fifth of all the fresh water that reaches the oceans
Largest lakeCaspian Sea, about 371,000 km² (143,000 sq mi) — salty and landlocked, counted as a lake
Largest freshwater lakeLake Superior, about 82,100 km² (31,700 sq mi), by area; Lake Baikal, Siberia, by volume — about a fifth of the world’s unfrozen fresh water
Deepest lakeLake Baikal, 1,642 m (5,387 ft) — also the oldest, about 25 million years
Highest navigable lakeTiticaca, Peru–Bolivia, 3,812 m (12,507 ft)
Largest islandGreenland, 2,166,086 km² (836,330 sq mi); Australia is counted as a continent
Largest archipelagoThe Malay Archipelago; Indonesia alone has more than 17,000 islands
Largest peninsulaThe Arabian Peninsula, about 3.2 million km² (1.25 million sq mi)
Largest bay and gulfThe Bay of Bengal, about 2.2 million km²; the Gulf of Mexico, about 1.6 million km²
Largest desertAntarctica, about 14.2 million km² (5.5 million sq mi) — a polar desert; the Sahara, about 9.2 million km² (3.6 million sq mi), is the largest hot desert
Largest rainforestThe Amazon, about 5.5 million km² (2.1 million sq mi) across nine countries
Longest mountain range on landThe Andes, about 7,000 km (4,350 mi) along South America’s western edge; the mid-ocean ridge system, about 65,000 km, is the longest of all
Highest mountain rangeThe Himalaya, with all fourteen of the world’s 8,000 m peaks together with the Karakoram
Highest volcanoOjos del Salado, Argentina–Chile, 6,893 m (22,615 ft); Mauna Loa in Hawaii is the largest active volcano by volume
Tallest waterfallAngel Falls, Venezuela, 979 m (3,212 ft)
Largest coral reefThe Great Barrier Reef, Australia, about 2,300 km (1,430 mi) long
Longest caveMammoth Cave, Kentucky, more than 685 km (426 mi) surveyed
Deepest caveVeryovkina Cave, Abkhazia, Georgia, 2,212 m (7,257 ft)
Largest deltaThe Ganges–Brahmaputra delta, Bangladesh and India, about 100,000 km² (39,000 sq mi)
Longest coastlineCanada, about 202,000 km (125,500 mi) including its islands
Highest capital cityLa Paz, Bolivia (seat of government), about 3,640 m (11,940 ft); Quito, Ecuador, is the highest constitutional capital at about 2,850 m

Countries

Sovereign states193 UN members, 2 UN observers, and a few states with limited recognition, such as Kosovo and Taiwan
Landlocked countries44, plus Liechtenstein and Uzbekistan, which are doubly landlocked — surrounded only by landlocked neighbors
Island countriesAbout 47, from Indonesia to Nauru
Most neighborsChina and Russia, 14 land neighbors each
Newest widely recognized stateSouth Sudan, independent July 9, 2011
Oldest republicSan Marino, by tradition founded in AD 301
Most populous city-stateSingapore, about 6 million
Most official languagesBolivia — 37; Zimbabwe — 16; India recognizes 22 scheduled languages
Most languages spokenPapua New Guinea, about 840 living languages
Countries on the equator13 — the equator crosses the land or waters of Ecuador, Colombia, Brazil, São Tomé and Príncipe, Gabon, Congo, DR Congo, Uganda, Kenya, Somalia, the Maldives, Indonesia and Kiribati
Countries with no armed forcesAbout 20, among them Costa Rica (since 1949), Iceland, Panama and Vatican City
First country to grant women the voteNew Zealand, 1893
Most time zonesFrance, 12; Russia spans 11 across one landmass
Largest empire in historyThe British Empire, about a quarter of the world’s land and people at its 1920s peak; the Mongol Empire was the largest contiguous
Highest life expectancyMonaco, Hong Kong and Japan, all above 84 years
Highest GDP per personLuxembourg, Ireland, Switzerland and Singapore, all above US$99,000 (2025); Monaco higher still among microstates
Most visited countryFrance — about 100 million international arrivals a year

People

PopulationAbout 8.3 billion (UN, 2026) — growing by roughly 70 million a year, about 0.85% and slowing
Population by continentAsia about 4.8 billion (60%); Africa about 1.5 billion; Europe about 745 million; Latin America and the Caribbean about 660 million; Northern America about 385 million; Oceania about 46 million
Births and deathsAbout 130 million births and 65 million deaths a year (UN, 2024)
Fertility rateAbout 2.2 children per woman (2025) — half the 1960s peak
Median ageAbout 31 years; projected to reach 36 by 2050
Life expectancy73.3 years (2024) — from about 47 in 1950
Sex ratioAbout 101 men for every 100 women
Urban populationAbout 58% — more than 4.8 billion people in cities; 35 or more megacities of over 10 million
Largest urban areasTokyo, Delhi, Shanghai, Dhaka, São Paulo, Cairo (UN, agglomerations)
Most spoken languagesEnglish, Mandarin Chinese, Hindi, Spanish, Arabic (all speakers); Mandarin, Spanish, English, Hindi, Bengali (native speakers)
Number of languagesAbout 7,000 living languages; roughly 40% are endangered
ReligionsChristians about 2.4 billion (31%), Muslims about 2 billion (25%), the religiously unaffiliated about 1.9 billion, Hindus about 1.2 billion, Buddhists about 500 million (Pew Research, 2020 baseline)
LiteracyAbout 87% of adults; about 92% of young people aged 15–24
Refugees and displaced peopleMore than 120 million forcibly displaced, the highest ever recorded (UNHCR, 2024)
Humans who have ever livedAbout 110–117 billion — the 8.3 billion alive today are roughly 7% of everyone who has ever been born

World economy

World GDP (nominal)About US$118 trillion (2025, IMF April 2026)
World GDP per personAbout US$14,000 (2025)
World growthAbout 3.3% a year (2025–26, IMF)
Largest economiesUnited States US$30.8 trillion · China US$19.6 trillion · Germany US$5.0 trillion · Japan US$4.4 trillion · United Kingdom US$4.0 trillion · India US$3.9 trillion (2025)
Largest economy by purchasing powerChina, ahead of the United States and India (IMF, PPP)
Fastest-growing major economyIndia, about 7–8% a year (2025)
Smallest economyTuvalu, about US$58 million (2025)
Richest per personLuxembourg, about US$148,000; Ireland about US$131,000; Switzerland about US$116,000 (2025); Monaco, a microstate, about US$288,000
Poorest per personBurundi, South Sudan, Afghanistan and Yemen, each below US$500 (2025)
Reserve currencyThe U.S. dollar — about 58% of central-bank foreign reserves; the euro second at about 20%
Largest trading nationChina — the largest exporter of goods; the United States the largest importer
Largest stock exchangeThe New York Stock Exchange, by the value of listed companies
Most traded commodityCrude oil — about 100 million barrels a day
World Trade Organization166 members; founded January 1, 1995, succeeding the GATT of 1947

Records & extremes

Hottest air temperature56.7 °C (134 °F), Furnace Creek, Death Valley, California, July 10, 1913
Coldest air temperature−89.2 °C (−128.6 °F), Vostok Station, Antarctica, July 21, 1983
Wettest placeMawsynram, Meghalaya, India — about 11,870 mm (467 in) of rain a year
Driest placeThe Atacama Desert, Chile — parts record no rain for years; the Dry Valleys of Antarctica are drier still
Windiest placeCommonwealth Bay, Antarctica — average winds above 80 km/h (50 mph)
Tallest buildingBurj Khalifa, Dubai, 828 m (2,717 ft), completed 2010
Longest bridgeDanyang–Kunshan Grand Bridge, China, 164.8 km (102.4 mi), on the Beijing–Shanghai railway
Longest wallThe Great Wall of China — about 21,196 km (13,171 mi) across all its sections
Longest tunnelThe Gotthard Base Tunnel, Switzerland, 57.1 km (35.5 mi), opened 2016
Longest railwayThe Trans-Siberian, Moscow to Vladivostok, 9,289 km (5,772 mi)
Busiest airportHartsfield–Jackson Atlanta International, more than 100 million passengers a year
Largest dam by powerThe Three Gorges Dam, China — 22,500 MW
Largest sports eventThe FIFA World Cup — the 2026 edition in the United States, Canada and Mexico, with 48 teams
Highest railwayThe Qinghai–Tibet line, China, reaching 5,072 m (16,640 ft) at the Tanggula Pass
Deepest mineMponeng gold mine, South Africa, about 4 km (2.5 mi) below the surface
Largest structure ever builtThe Great Wall of China; by volume, the Great Pyramid of Giza was the tallest structure for more than 3,800 years

History in dates

c. 300,000 years agoHomo sapiens emerges in Africa
c. 10,000 BCFarming begins in the Fertile Crescent
c. 3200 BCWriting appears in Mesopotamia and Egypt
1 billion peopleAbout 1804
2 billion1927 · 3 billion — 1960 · 4 billion — 1974
5 billion1987 · 6 billion — 1999 · 7 billion — 2011
8 billionNovember 15, 2022 — the UN’s Day of Eight Billion
1492Columbus reaches the Americas
1522Magellan’s expedition completes the first circumnavigation of the world
1893New Zealand becomes the first country to give women the vote
1945The United Nations founded, October 24
1961Yuri Gagarin, the first human in space, April 12
1969Neil Armstrong and Buzz Aldrin walk on the Moon, July 20
1989–91The Berlin Wall falls; the Soviet Union dissolves, December 26, 1991
2011South Sudan, the newest widely recognized state
2050Projected world population about 9.7 billion; a peak near 10.3 billion in the 2080s (UN, medium variant)

Frequently asked questions

How many countries are there in the world?

The United Nations has 193 member states and two observer states, the Holy See and Palestine — the count most references use, 195. A handful of other territories are recognized by some countries but not by the UN, such as Kosovo and Taiwan, which is why totals in different sources range from 193 to about 200.

What is the population of the world?

About 8.3 billion people in 2026, by the UN’s World Population Prospects. India is the most populous country at about 1.46 billion, ahead of China at about 1.41 billion; the two together hold roughly a third of humanity. The UN projects about 9.7 billion people by 2050 and a peak near 10.3 billion in the 2080s.

What are the highest and lowest points on Earth?

Mount Everest, 8,848.86 m (29,032 ft), on the Nepal–China border, is the highest point above sea level; the shore of the Dead Sea, about 430 m (1,410 ft) below sea level and falling each year, is the lowest exposed land. The deepest point of all is the Challenger Deep in the Pacific’s Mariana Trench, about 10,935 m (35,876 ft) down, though surveys differ by a few dozen meters.

What is the longest river in the world?

By the traditional count the Nile, about 6,650 km (4,130 mi) from its remotest source to the Mediterranean. Some researchers measure the Amazon at 6,400 km or more and, including its tidal estuary, longer than the Nile; a 2009 peer-reviewed study found the Nile longer. The Amazon carries far more water than any other river.

Which country is the largest, and which the smallest?

Russia, at about 17.1 million km² (6.6 million sq mi), covers more than a tenth of the world’s land; Vatican City, at 0.44 km² (0.17 sq mi), is the smallest independent state. By population the extremes are India and Vatican City again, whose residents number in the hundreds.

How big is the world economy?

About US$118 trillion in 2025 by the IMF’s April 2026 estimates — roughly US$14,000 per person. The United States is the largest economy at about US$30.8 trillion, China second at about US$19.6 trillion; Germany, Japan and the United Kingdom follow, with India sixth at about US$3.9 trillion.

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