ContinentA continent is any of several large geographical regions. Continents are generally identified by convention rather than any strict criteria. A continent could be a single landmass or a part of a very large landmass, as in the case of Asia or Europe. Due to this, the number of continents varies; up to seven or as few as four geographical regions are commonly regarded as continents. Most English-speaking countries recognize seven regions as continents.
EurasiaEurasia (jʊəˈreɪʒə, alsoUK-S@) is the largest continental area on Earth, comprising all of Europe and Asia. According to some geographers, physiographically, Eurasia is a single continent. The concepts of Europe and Asia as distinct continents date back to antiquity, but their borders are arbitrary and have historically been subject to change. Eurasia is connected to Africa at the Suez Canal, and the two are sometimes combined to describe the largest contiguous landmass on Earth, Afro-Eurasia.
Borders of the oceansThe borders of the oceans are the limits of Earth's oceanic waters. The definition and number of oceans can vary depending on the adopted criteria. The principal divisions (in descending order of area) of the five oceans are the Pacific Ocean, Atlantic Ocean, Indian Ocean, Southern (Antarctic) Ocean, and Arctic Ocean. Smaller regions of the oceans are called seas, gulfs, bays, straits, and other terms. Geologically, an ocean is an area of oceanic crust covered by water.
Ethnic groups in EuropeEuropeans are the focus of European ethnology, the field of anthropology related to the various ethnic groups that reside in the states of Europe. Groups may be defined by common genetic ancestry, common language, or both. The total number of national minority populations in Europe is estimated at 105 million people, or 14% of 770 million Europeans. The Russians are the most populous among Europeans, with a population of roughly 120 million. There are no universally accepted and precise definitions of the terms "ethnic group" and "nationality".
Afro-EurasiaAfro-Eurasia (also Afroeurasia, Eurafrasia, Africa-Eurasia or the Old World) is a landmass comprising the continents of Africa, Asia, and Europe. The terms are compound words of the names of its constituent parts. Its mainland is the largest and most populous contiguous landmass on Earth. Afro-Eurasia encompasses , 57% of the world's land area, and has a population of approximately 6.7 billion people, roughly 86% of the world population.