Asia
Asia is the largest and most populous continent or region, depending on the definition. It covers 8.6% of the Earth's total surface area, or 29.4% of its land area, and it contains more than 60% of the world's human population.
Asia is traditionally defined as part of the landmass of Africa-Eurasia – with the western portion of the latter occupied by Europe – lying east of the Suez Canal, east of the Ural Mountains, and south of the Caucasus Mountains and the Caspian and Black Seas.
Medieval Europeans considered Asia as a continent – a distinct landmass. The European concept of the three continents in the Old World goes back to Classical Antiquity, but during the Middle Ages was notably due to Isidore of Sevilla (see T and O map). The demarcation between Asia and Africa is the Isthmus of Suez and the Red Sea. The boundary between Asia and Europe is commonly considered to run through the Dardanelles, the Sea of Marmara, the Bosporus, the Black Sea, the Caucasus Mountains, the Caspian Sea, the Ural River to its source, and the Ural Mountains to the Kara Sea near Kara, Russia. While this interpretation of tripartite continents (i.e., of Asia, Europe, and Africa) remains common in modernity, discovery of the extent of Africa and Asia have made this definition somewhat anachronistic. This is especially true in the case of Asia, which would have several regions that would be considered distinct landmasses if these criteria were used (for example, Southern Asia and Eastern Asia).
Generally, geologists and physical geographers do not consider Asia and Europe to be separate continents. Physiographically, Asia is the major eastern constituent of the continent of Eurasia – with Europe being a northwestern peninsula of the landmass – or of Africa-Eurasia: geologically, Asia, Europe, and Africa comprise a single continuous landmass (save the Suez Canal) and share a common continental shelf. Almost all of Europe and most of Asia sit atop the Eurasian Plate, adjoined on the south by the Arabian and Indian Plates, and with much of Siberia situated on the North American Plate.
In geography, there are two schools of thought. One school follows historical convention and treats Europe and Asia as different continents, categorizing subregions within them for more detailed analysis. The other school equates the word "continent" with a geographical region when referring to Europe, and use the term "region" to describe Asia in terms of physiography. Since, in linguistic terms, "continent" implies a distinct landmass, it is becoming increasingly common to substitute the term "region" for "continent" to avoid the problem of disambiguation altogether.
Given the scope and diversity of the landmass, it is sometimes not even clear exactly what "Asia" consists of. Some definitions exclude Turkey, the Middle East, Central Asia and Russia while only considering the Far East, Southeast Asia and the Indian Subcontinent to compose Asia. The term is sometimes used more strictly in reference to the Asia-Pacific region, which does not include the Middle East or Russia, but does include islands in the Pacific Ocean — a number of which may also be considered part of Australasia or Oceania although Pacific Islanders are commonly not considered Asian.
Geography
Medieval Europeans considered Asia as a continent, a distinct landmass. The European concept of the three continents in the Old World goes back to classical antiquity with the etymology of the word rooted in the ancient Near and Middle East. The demarcation between Asia and Africa is the Isthmus of Suez and the Red Sea. The boundary between Asia and Europe is commonly believed to run through the Dardanelles, the Sea of Marmara, the Bosporus, the Black Sea, the Caucasus Mountains, the Caspian Sea, the Ural River to its source, and the Ural Mountains to the Kara Sea near Kara, Russia. However, modern discovery of the extent of Africa and Asia made this definition rather anachronistic, especially in the case of Asia, which would have several regions that would be considered distinct landmasses if these criteria were used (for example, South Asia and East Asia).
Geologists and physical geographers no longer consider Asia and Europe to be separate continents. It is either defined in terms of geological landmasses (physical geography) or tectonic plates (geology). In the former case, Europe is a western peninsula of Eurasia or the Africa-Eurasia landmass. In the latter, Europe and Asia are parts of the Eurasian plate, which excludes the Arabian and Indian tectonic plates.
In human geography, there are two schools of thought. One school follows historical convention and treats Europe and Asia as different continents, categorizing Europe, East Asia (The Orient), South Asia (British India), and the Middle East (Arabia and Persia) as specific regions for more detailed analysis. The other schools equate the word "continent" in terms of geographical region when referring to Europe, and use the term "region" to describe Asia in terms of physical geography. Because in linguistic terms, "continent" implies a distinct landmass, it is becoming increasingly common to substitute the term "region" for "continent" to avoid the problem of disambiguation altogether.
There is much confusion in European languages with the term "Asian". Because a category implies homogenity, the term "Asian" almost always refers to a subcategory of people from Asia rather than referring to "Asian" defined in term of "Asia". The fact that in American English, Asian refers to East Asian (Orientals), while in British English, Asian refers to South Asian reflects this confusion. Sometimes, it is not even clear exactly what "Asia" consists of. Some definitions exclude Turkey, the Middle East, or Russia. The term is sometimes used more strictly in reference to Asia Pacific, which does not include the Middle East or Russia, but does include islands in the Pacific Ocean — a number of which may also be considered part of Australasia or Oceania. Asia contains the Indian subcontinent, Arabian subcontinent, as well as a piece of the North American plate in Siberia.
The mean elevation of the continent is 950 m (3,117 ft.), the highest of any in the world. The plateau and mountainous areas broadly sweep SW-NW across Asia, climaxing in the high Tibetan Plateau, rising to the highest peaks in the world in the Himalaya. To the north west lie plains, while to the south lie the geologically distinct areas of the Arabian peninsula, Indian subcontinent and Malay peninsula. Large numbers of islands lie south east of the continent.
Besides its mainland, Asia includes a large number of islands, including some of the world's largest islands, such as Borneo and Sumatra, and some of the world's most populated islands, such as Java and Honshū.
Other famous islands include Bali, Madura and Sulawesi of Indonesia; Hokkaidō, Shikoku, Kyūshū and Okinawa of Japan; the Andaman and Nicobar of India; Luzon, Cebu and Mindanao of the Philippines; Ko Pha Ngan and Ko Samui of Thailand; as well as Sri Lanka, Maldives, Singapore, Hong Kong island and Sakhalin.
The Asian nations of Indonesia, Brunei, East Timor, Singapore, Japan, Philippines, Taiwan, Sri Lanka, Maldives and Cyprus are solely made up of one or more islands, and have no territory on the mainland.
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