20th century

[1][2] It was the 10th and last century of the 2nd millennium and was marked by new models of scientific understanding, unprecedented scopes of warfare, new modes of communication that would operate at nearly instant speeds, and new forms of art and entertainment.

Poverty was reduced and the century saw rising standards of living, world population growth, awareness of environmental degradation and ecological extinction.

These developments were made possible by the exploitation of fossil fuel resources, which offered energy in an easily portable form, but also caused concern about pollution and long-term impact on the environment.

In addition to annexing many of the colonial possessions of the vanquished states, the Triple Entente exacted punitive restitution payments from them, plunging Germany in particular into economic depression.

Japan's military expansionism in East Asia and the Pacific Ocean brought it into conflict with the United States, culminating in a surprise attack which drew the US into World War II.

After the victory of the Allies in Europe, the war in Asia ended with the Soviet invasion of Manchuria and the dropping of two atomic bombs on Japan by the US, the first nation to develop nuclear weapons and the only one to use them in warfare.

Peacekeeping forces consisting of troops provided by various countries, with various United Nations and other aid agencies, helped to relieve famine, disease, and poverty, and to suppress some local armed conflicts.

Western Europe was rebuilt with the aid of the American Marshall Plan, resulting in a major post-war economic boom, and many of the affected nations became close allies of the United States.

Allies during the war, they soon became hostile to one another as their competing ideologies of communism and democratic capitalism proliferated in Europe, which became divided by the Iron Curtain and the Berlin Wall.

Unable to engage one another directly, the conflict played out in a series of proxy wars around the world—particularly in China, Korea, Cuba, Vietnam, and Afghanistan—as the USSR sought to export communism while the US attempted to contain it.

The technological competition between the two sides led to substantial investment in research and development which produced innovations that reached far beyond the battlefield, such as space exploration and the Internet.

[8][9][10] After the Soviet Union collapsed under internal pressure in 1991, most of the communist governments it had supported around the world were dismantled—with the notable exceptions of China, North Korea, Cuba, Vietnam, and Laos—followed by difficult transitions into market economies.

[11] Due to continuing industrialization and expanding trade, many significant changes of the century were, directly or indirectly, economic and technological in nature.

Inventions such as the light bulb, the automobile, mechanical computers, and the telephone in the late 19th century, followed by supertankers; airliners; motorways; radio communication and broadcasting; television; digital computers; air conditioning; antibiotics; nuclear power; frozen food; microcomputers; the Internet and the World Wide Web; and mobile telephones affected people's quality of life across the developed world.

Although the Atlantic slave trade had ended in the 19th century, movements for equality for non-white people in the white-dominated societies of North America, Europe, and South Africa continued.

By the end of the 20th century, in many parts of the world, women had the same legal rights as men, and racism had come to be seen as unacceptable, a sentiment often backed up by legislation.

[16] One argument is that of global warming occurring due to human-caused emission of greenhouse gases, particularly carbon dioxide produced by the burning of fossil fuels.

[20] According to Charles Tilly, "Altogether, about 100 million people died as a direct result of action by organized military units backed by one government or another over the course of the century.

Video games—due to the great technological steps forward in computing since the second post-war period—are one of the new forms of entertainment that emerged in the 20th century alongside films.

In the first part of the 20th century, measure theory, functional analysis, and topology were established, and significant developments were made in fields such as abstract algebra and probability.

Earthrise , taken on December 24, 1968 by astronaut William "Bill" Anders during the Apollo 8 space mission. It was the first photograph taken of Earth from lunar orbit .
World powers and empires in 1914, just before the First World War.
The mushroom cloud of the detonation of Little Boy , the first nuclear attack in history, on 6 August 1945 over Hiroshima , igniting the nuclear age with the international security dominating thread of mutual assured destruction in the latter half of the 20th century.
The international community grew in the second half of the century significantly due to a new wave of decolonization, particularly in Africa. Most of the newly independent states, were grouped together with many other so called developing countries . Developing countries gained attention, particularly due to rapid population growth, leading to a record world population of nearly 7 billion people by the end of the century.
Martin Luther King Jr. , an African American civil rights movement leader ( Washington, August 1963 )
The Blue Marble , Earth as seen from Apollo 17 in December 1972. The photograph was taken by LMP Harrison Schmitt . The second half of the 20th century saw humanity's first space exploration .
Map of territorial changes in Europe after World War I (as of 1923).
Richard Nixon and Leonid Brezhnev aboard the USS Sequoia , June 19, 1973
Hong Kong , under British administration from 1842 to 1997, is one of the original Four Asian Tigers .
I and the Village , 1911, by Marc Chagall , a modern painter
Elvis Presley in 1956, a leading figure of rock and roll and rockabilly .
Charlie Chaplin in his 1921 film The Kid , with Jackie Coogan .
Ralph Baer 's Magnavox Odyssey , the first video game console, released in 1972.
The Empire State Building is an iconic building of the 1930s.
The pioneer of computer science , Alan Turing
Wheat yields greatly increased from the Green Revolution in the world's least developed countries .
A stamp commemorating Alexander Fleming . His discovery of penicillin changed the world of medicine by introducing the age of antibiotics.
Oil field in California, 1938. The first modern oil well was drilled in 1848 by Russian engineer F.N. Semyonov, on the Apsheron Peninsula north-east of Baku .
First flight of the Wright brothers ' Wright Flyer on December 17, 1903, in Kitty Hawk, North Carolina ; Orville piloting with Wilbur running at wingtip.
Photo of American astronaut Buzz Aldrin during the first moonwalk in 1969, taken by Neil Armstrong . The relatively young aerospace engineering industries rapidly grew in the 66 years after the Wright brothers' first flight.