Antarctica in the context of "Dome C"

A continent is any of several large terrestrial geographical regions. Continents are generally identified by convention rather than any strict criteria. A continent could be a single large landmass, a landmass and nearby islands either on or beyond its continental shelf, or a part of a larger landmass, as in the case of Asia and Europe within Eurasia. Due to these varying definitions, the number of continents varies, up to seven or as few as four. Most English-speaking countries recognize seven continents. In order from largest to smallest in area, these seven are Asia, Africa, North America, South America, Antarctica, Europe, and Australia (or sometimes Oceania or Australasia). Different variations with fewer continents merge some of these regions; examples of this are merging Asia and Europe into Eurasia, North America and South America into the Americas (or simply America), and Africa, Asia, and Europe into Afro-Eurasia.

Oceanic islands are occasionally grouped with a nearby continent to divide all the world's land into geographical regions. Under this scheme, most of the island countries and territories in the Pacific Ocean are grouped together with the continent of Australia to form the geographical region of Oceania.

Human history or world history is the record of humankind from prehistory to the present. Modern humans evolved in Africa around 300,000 years ago and initially lived as hunter-gatherers. They migrated out of Africa during the Last Ice Age and had spread to every continent except Antarctica by the end of the Ice Age 12,000 years ago. Soon afterward, the Neolithic Revolution in West Asia brought the first systematic husbandry of plants and animals, and saw many humans transition from nomadic lives to sedentary existences as farmers in permanent settlements. The growing complexity of human societies necessitated systems of accounting and writing.

These developments paved the way for the emergence of early civilizations in Mesopotamia, Egypt, Peru, the Indus Valley, and China, marking the beginning of the ancient period in the 4th millenium BCE. These civilizations enabled the establishment of regional empires and provided fertile ground for the advent of transformative philosophical and religious ideas. Hinduism originated during the late Bronze Age and was followed by the many seminal belief systems of the Axial Age: Buddhism, Confucianism, Greek philosophy, Jainism, Judaism, Taoism, and Zoroastrianism. Christianity began later as an offshoot of Judaism. The subsequent post-classical period, from about 500 to 1500 CE, witnessed the rise of Islam and China's flourishing under the Tang and Song dynasties while civilization expanded to new parts of the world and trade between societies increased. The political landscape was shaped by the rise and fall of major empires, such as the Byzantine Empire, the Islamic caliphates, and the Mongol Empire. This period's invention of gunpowder and the printing press greatly affected later history.

An island country, island state, or island nation is a country whose primary territory consists of one or more islands or parts of islands. Approximately 25% of all independent countries are island countries. Island countries are historically more stable than many continental states but are vulnerable to conquest by naval superpowers. Indonesia is the largest and most populated island country in the world (and the fourth most populated country overall).

There are great variations between island country economies: they may rely mainly on extractive industries, such as mining, fishing and agriculture, and/or on services such as transit hubs, tourism, and financial services. Many islands have low-lying geographies and their economies and population centers develop along coast plains and ports; such states may be vulnerable to the effects of climate change, especially sea level rise.

The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is bounded by the continents of Asia and Australia in the west and the Americas in the east.

At 165,250,000 square kilometers (63,800,000 square miles) in area (as defined with a southern Antarctic border), the Pacific Ocean is the largest division of the World Ocean and the hydrosphere and covers approximately 46% of Earth's water surface and about 32% of the planet's total surface area, larger than its entire land area (148,000,000 km (57,000,000 sq mi)). The centers of both the water hemisphere and the Western Hemisphere, as well as the oceanic pole of inaccessibility, are in the Pacific Ocean. Ocean circulation (caused by the Coriolis effect) subdivides it into two largely independent volumes of water that meet at the equator, the North Pacific Ocean and the South Pacific Ocean (or more loosely the South Seas). The Pacific Ocean can also be informally divided by the International Date Line into the East Pacific and the West Pacific, which allows it to be further divided into four quadrants, namely the Northeast Pacific off the coasts of North America, the Southeast Pacific off South America, the Northwest Pacific off Far Eastern/Pacific Asia, and the Southwest Pacific around Oceania.

The United Nations comprise 193 sovereign states and the world's largest intergovernmental organization. All members have equal representation in the United Nations General Assembly.

The Charter of the United Nations defines the rules for admission of member states. Membership is open to all states which accept certain terms of the charter and are able to carry them out. New members must be recommended by the United Nations Security Council. In addition to the member states, the UN also invites non-member states to be observer states at the UN General Assembly. A member state that has persistently violated the principles of the United Nations Charter can be expelled from the United Nations.

The Veleka (Bulgarian: Велека [vɛˈlɛkɐ], Turkish: Kocadere [koˈd͡ʒadeɾe]) is a river in the very southeast of Bulgaria, as well as the very northeast of European Turkey. It is 147 km long, of which 108 km lie in Bulgaria and 25 km are in Turkey. It flows into the Black Sea at the Bulgarian village of Sinemorets. Veleka Ridge on Livingston Island in the South Shetland Islands, Antarctica is named after the river.

Determining the boundaries between the continents is generally a matter of geographical convention and consensus. Several slightly different conventions are in use. The number of continents is most commonly considered seven (in English-speaking countries) but may range as low as four when Afro-Eurasia and the Americas are both considered as single continents. An island can be considered to be associated with a given continent by either lying on the continent's adjacent continental shelf (e.g. Singapore, the British Isles) or being a part of a microcontinent on the same principal tectonic plate (e.g. Madagascar and Seychelles). An island can also be entirely oceanic while still being associated with a continent by geology (e.g. Bermuda, the Australian Indian Ocean Territories) or by common geopolitical convention (e.g. Ascension Island, the South Sandwich Islands). Another example is the grouping into Oceania of the Pacific Islands with Australia and Zealandia.

There are three overland boundaries subject to definition:

Oceania (UK: /ˌoʊsiˈɑːniə, ˌoʊʃi-, -ˈeɪn-/ OH-s(h)ee-AH-nee-ə, -⁠AY-, US: /ˌoʊʃiˈæniə, -ˈɑːn-/ OH-shee-A(H)N-ee-ə) is a geographical region including Australasia, Melanesia, Micronesia, and Polynesia. Outside of the English-speaking world, Oceania is generally considered a continent, while Mainland Australia is regarded as its continental landmass. Spanning the Eastern and Western hemispheres, at the centre of the water hemisphere, Oceania is estimated to have a land area of about 9,000,000 square kilometres (3,500,000 sq mi) and a population of around 46.3 million as of 2024. Oceania is the smallest continent in land area and the second-least populated after Antarctica.

Oceania has a diverse mix of economies from the highly developed and globally competitive financial markets of Australia, French Polynesia, Hawaii, New Caledonia, and New Zealand, which rank high in quality of life and Human Development Index, to the much less developed economies of Kiribati, Papua New Guinea, Tuvalu, Vanuatu, and Western New Guinea. The largest and most populous country in Oceania is Australia, and the largest city is Sydney. Puncak Jaya in Indonesia is the highest peak in Oceania at 4,884 m (16,024 ft).

South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern subregion of the Americas.

South America is bordered on the west by the Pacific Ocean, on the north and east by the Atlantic Ocean, and to the south by the Drake Passage; North America, the Caribbean Sea lying to the northwest, and the Antarctic Circle, Antarctica, and the Antarctic Peninsula to the south.