Abrahamic religionsThe Abrahamic religions are a group of religions centered around the worship of the God of Abraham. Abraham, a Hebrew patriarch, is extensively mentioned throughout the Abrahamic religious scriptures of the Quran, and the Hebrew and Christian Bibles. Jewish tradition claims that the Twelve Tribes of Israel are descended from Abraham through his son Isaac and grandson Jacob, whose sons formed the nation of the Israelites in Canaan (or the Land of Israel); Islamic tradition claims that twelve Arab tribes known as the Ishmaelites are descended from Abraham through his son Ishmael in the Arabian Peninsula.
World warA world war is an international conflict that involves most or all of the world's major powers. Conventionally, the term is reserved for the two major international conflicts that occurred during the first half of the 20th century, World War I (1914–1918) and World War II (1939–1945), although some historians have also described other global conflicts as world wars, such as the Nine Years' War, the War of the Spanish Succession, the Seven Years' War, the French Revolutionary and Napoleonic Wars, the Cold War, and the War on Terror.
Politics of the United StatesIn the United States, politics function within a framework of a constitutional federal republic and presidential system, with three distinct branches that share powers: the U.S. Congress which forms the legislative branch, a bicameral legislative body comprising the House of Representatives and the Senate; the executive branch, which is headed by the president of the United States, who serves as the country's head of state and government; and the judicial branch, composed of the Supreme Court and lower federal courts, and which exercises judicial power.
PaintingPainting is the practice of applying paint, pigment, color or other medium to a solid surface (called the "matrix" or "support"). The medium is commonly applied to the base with a brush, but other implements, such as knives, sponges, and airbrushes, can be used. In art, the term "painting" describes both the act and the result of the action (the final work is called "a painting").
DemocracyDemocracy (from dēmokratía, dēmos 'people' and kratos 'rule') is a system of government and form of liberalism in which state power is vested in the people, or the general population of a state based on principles of liberty and free will. According to the United Nations, democracy "provides an environment that respects human rights and fundamental freedoms, and in which the freely expressed will of people is exercised." In a direct democracy, the people have the direct authority to deliberate and decide legislation.
Economic systemsAn economic system, or economic order, is a system of production, resource allocation and distribution of goods and services within a society. It includes the combination of the various institutions, agencies, entities, decision-making processes, and patterns of consumption that comprise the economic structure of a given community. An economic system is a type of social system. The mode of production is a related concept.
Global citiesA megalopolis (ˌmɛgəˈlɒpəlɪs) or a supercity, also called a megaregion, is a group of metropolitan areas which are perceived as a continuous urban area through common systems of transport, economy, resources, ecology, and so on. They are integrated enough that coordinating policy is valuable, although the constituent metropolises keep their individual identities. The megalopolis concept has become highly influential as it introduced a new, larger scale thinking about urban patterns and growth.
Geography of North AmericaNorth America is the third largest continent, and is also a portion of the third largest supercontinent if North and South America are combined into the Americas and Africa, Europe, and Asia are considered to be part of one supercontinent called Afro-Eurasia. With an estimated population of 580 million and an area of 24,709,000 km2 (9,540,000 mi2), the northernmost of the two continents of the Western Hemisphere is bounded by the Pacific Ocean on the west; the Atlantic Ocean on the east; the Caribbean Sea on the south; and the Arctic Ocean on the north.
SpacecraftsA spacecraft (: spacecraft) is a vehicle that is designed to fly in outer space and operate there. Spacecraft are used for a variety of purposes, including communications, Earth observation, meteorology, navigation, space colonization, planetary exploration, and transportation of humans and cargo. All spacecraft except single-stage-to-orbit vehicles cannot get into space on their own, and require a launch vehicle (carrier rocket).
History of scienceThe history of science covers the development of science from ancient times to the present. It encompasses all three major branches of science: natural, social, and formal. Science's earliest roots can be traced to Ancient Egypt and Mesopotamia around 3000 to 1200 BCE. These civilizations' contributions to mathematics, astronomy, and medicine influenced later Greek natural philosophy of classical antiquity, wherein formal attempts were made to provide explanations of events in the physical world based on natural causes.