Africa

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:

The North Atlantic Gyre of the Atlantic Ocean is one of five great oceanic gyres. It is a circular ocean current, with offshoot eddies and sub-gyres, across the North Atlantic from the Intertropical Convergence Zone (calms or doldrums) to the part south of Iceland, and from the east coasts of North America to the west coasts of Europe and Africa.

In turn it is chiefly subdivided into the Gulf Stream flowing northward along the west; its often conflated continuation, the North Atlantic Current across the north; the Canary Current flowing southward along the east; and the Atlantic's North Equatorial Current in the south. The gyre has a pronounced thermohaline circulation, bringing salty water west from the Mediterranean Sea and then north to form the North Atlantic Deep Water.

Modern English, sometimes called New English (NE) or present-day English (PDE) as opposed to Middle and Old English, is the form of the English language that has been spoken since the Great Vowel Shift in England, which began in the late 14th century and was completed by the 17th century.

With some differences in vocabulary, texts that date from the early 17th century, such as the works of William Shakespeare and the King James Bible, are considered Modern English, or more specifically, Early Modern English or Elizabethan English. Through colonization, the British Empire spread English to many regions of the world, such as Anglo-America, the Indian subcontinent, Africa, Australia and New Zealand.

Antarctic flora are a distinct community of vascular plants which evolved millions of years ago on the supercontinent of Gondwana. In 2025, species of Antarctica flora reside on several now separated areas of the Southern Hemisphere, including southern South America, southernmost Africa, New Zealand, Australia, and New Caledonia. Joseph Dalton Hooker (1817 – 1911) was the first to notice similarities in the flora and speculated that Antarctica had served as either a source or a transitional point, and that land masses now separated might formerly have been adjacent.

Based on the similarities in their flora, botanist Ronald D'Oyley Good identified a separate Antarctic Floristic Kingdom that included southern South America, New Zealand, and some southern island groups. In addition, Australia was determined to be its own floristic kingdom because of the influx of tropical Eurasian flora that had mostly supplanted the Antarctic flora and included New Guinea and New Caledonia in the Paleotropical floristic kingdom.

The aftermath of World War II saw the rise of two global superpowers, the United States (U.S.) and the Soviet Union (USSR). The aftermath of World War II was also defined by the rising threat of nuclear warfare, the creation and implementation of the United Nations as an intergovernmental organization, and the decolonization of Asia, Oceania, South America and Africa by European and East Asian powers, most notably by the United Kingdom, France, and Japan.

Once allies during World War II, the U.S. and the U.S.S.R. became competitors on the world stage and engaged in the Cold War, so called because it never resulted in overt, declared total war between the two powers. It was instead characterized by espionage, political subversion and proxy wars. Western Europe was rebuilt through the American Marshall Plan, whereas Central and Eastern Europe fell under the Soviet sphere of influence and eventually behind an "Iron Curtain". Europe was divided into a U.S.-led Western Bloc and a Soviet-led Eastern Bloc. Internationally, alliances with the two blocs gradually shifted, with some nations trying to stay out of the Cold War through the Non-Aligned Movement. The Cold War also saw a nuclear arms race between the two superpowers, and part of the reason that the Cold War never became a "hot" war was that the Soviet Union and the United States had nuclear deterrents against each other, leading to a mutually assured destruction standoff.

A fixed price is a price designated for a good or a service that is neither subject to bargaining nor bartering. The price may be fixed since the seller has placed it, or given that the price is managed by the authorities under price regulation. Fixed prices may also refer to swaps whereby payments are determined upon a never-ending interest rate, if not referring to negotiated price points that aren't amendable under regular situations. These also extend towards fixed-price contracts, whereas the price is not permitted to fluctuate unless there are premeditated mitigating situations; The equivalents of these, by definition, are cost-plus contracts, where the contractor-originating costs are managed, likewise with additional revenue subsidies issued.

Bargaining is very common in many parts of the world, primarily in the Middle East, Africa as well as Asia but not in most retail stores in Europe, North America, and Japan. Elsewhere, fixed prices tend to be an exception from the norm. Before the introduction of currency, both practices were the universally accepted means of transaction, at a domestic and international rate.

The Common Market for Eastern and Southern Africa (COMESA) is a regional economic community in Africa with twenty-one member states stretching from Tunisia to Eswatini. COMESA was formed in December 1994, replacing a Preferential Trade Area which had existed since 1981. Nine of the member states formed a free trade area in 2000 (Djibouti, Egypt, Kenya, Madagascar, Malawi, Mauritius, Sudan, Zambia and Zimbabwe), with Rwanda and Burundi joining the FTA in 2004, the Comoros and Libya in 2006, Seychelles in 2009, Uganda in 2012 and Tunisia in 2018.

COMESA is one of the pillars of the African Economic Community.

The African plate, also known as the Nubian plate, is a major tectonic plate that includes most of the continent of Africa (except for its easternmost part) and the adjacent oceanic crust to the west and south. It also includes a narrow strip of Western Asia along the Mediterranean Sea, including much of Israel and Lebanon. It is bounded by the North American plate and South American plate to the west (separated by the Mid-Atlantic Ridge); the Arabian plate and Somali plate to the east; the Eurasian plate, Aegean Sea plate and Anatolian plate to the north; and the Antarctic plate to the south.

Between 60 million years ago and 10 million years ago, the Somali plate began rifting from the African plate along the East African Rift. Since the continent of Africa consists of crust from both the African and the Somali plates, some literature refers to the African plate as the Nubian plate to distinguish it from the continent as a whole.

North Africa is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region. However, it is sometimes defined as stretching from the Atlantic shores of the Western Sahara in the west, to Egypt and Sudan's Red Sea coast in the east.

The most common definition for the region's boundaries includes Algeria, Egypt, Libya, Morocco, Tunisia, and Western Sahara, the territory disputed between Morocco and the partially recognized Sahrawi Arab Democratic Republic. The United Nations’ definition includes all these countries as well as Sudan. The African Union defines the region similarly, only differing from the UN in excluding the Sudan and including Mauritania. The Sahel, south of the Sahara Desert, can be considered as the southern boundary of North Africa. North Africa includes the Spanish cities of Ceuta and Melilla, and the plazas de soberanía. It can also be considered to include Malta, as well as other Italian, Portuguese, and Spanish regions such as Lampedusa and Lampione, Madeira, and the Canary Islands, which are all either closer to the African continent than Europe or as close to the African continent as Europe.

Homo (from Latin homō 'human') is a genus of great ape (family Hominidae) that emerged from the early homininian genus Australopithecus, encompassing a single extant species, Homo sapiens (modern humans), along with a number of extinct species (e.g. Homo erectus and Homo neanderthalensis) classified as either ancestral or closely related to modern humans, collectively called archaic humans. Homo, together with the genus Paranthropus, is probably most closely related to the species Australopithecus africanus within Australopithecus. The closest living relatives of Homo are of the hominin genus Pan (chimpanzees and bonobos), with the ancestors of Pan and Homo estimated to have diverged around 5.7–11 million years ago during the Late Miocene.

The oldest member of the genus is Homo habilis, with fossil records of just over 2 million years ago. H. erectus appeared about 2 million years ago and spread throughout Africa (debatably as another species called Homo ergaster) and Eurasia in several migrations. The species was adaptive and successful, and persisted for more than a million years before gradually diverging into new species around 500,000 years ago.