The 20th century of the Common Era began on January 1, 1901 and ended on December 31, 2000, according to the Gregorian calendar.It was during this time that the British Empire and the German Empire ended. The century saw a remarkable shift in the way that vast numbers of people lived as a result of technological, medical, social, ideological, and political innovation. Terms like ideology, world war, genocide, and nuclear war entered common usage. Scientific discoveries, such as the theory of relativity and quantum physics, drastically changed the world-view of scientists, causing them to realize that the universe was fantastically more complex than previously believed, and dashing the hopes at the end of the 19th century that the last few details of scientific knowledge were about to be filled in. Accelerating scientific understanding, more efficient communications, and faster transportation transformed the world in those hundred years more rapidly and widely than at any time in the past. It was a century that started with steam-powered ships and ended with the space shuttle. Horses and other pack animals, Western society's basic form of personal transportation for thousands of years, were replaced by automobiles within the span of a few decades. These developments were made possible by the large-scale exploitation of fossil fuel resources (especially petroleum), which offered great amounts of energy in an easily portable and storable form, but also caused widespread concerns about pollution and our long-term impact on the environment. Humanity explored outer space for the first time, even taking their first footsteps on the Moon.

Mass media, telecommunications, and information technology (especially the Internet) put the world's knowledge at the disposal of many in the most industrialized societies and some in developing countries as well. Many people's view of the world changed significantly as they became much more aware of the suffering and struggles of others and, as such, became increasingly concerned with human rights. In the latter half of the century especially, mankind became aware of the vast scale on which it had affected the planet, and took steps to minimize its damage of the planet's fragile ecosystems. Advancements in medical technology also improved the welfare of many people on the planet; life expectancy increased dramatically from the mid-30s to the mid-60s worldwide during the century. The healthiest countries had life expectancies of over 80 years by the turn of the millennium. Rapid technological advancements, however, also allowed warfare to reach an unprecedented high; World War II alone killed over 60 million people, while nuclear weaponry gave humankind the means to destroy itself in a very short period of time. The world also became more culturally homogenized than ever with developments in transportation and communications technology, popular music and other influences of Western culture, international corporations, and what was arguably a true global economy by the end of the century.

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• 1990s (2)

• Art@ (356)
• Atomic Age (90)
• Burma-Shave@ (22)
• Cold War (123)
• Computers@ (367)
• Cultural Events (2)
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• Fashion@ (1)
• Gay, Lesbian, and Bisexual@ (75)
• Genocide (13)

• Great Depression (20)
• Holocaust (339)
• Internet@ (99)
• People (10)
• Philosophy@ (46)
• Television@ (49)
• Terrorism@ (851)
• War Crimes@ (132)
• Wars and Conflicts (1,856)

See also:

• Recreation: Living History: By Time Period: 20th Century (116)
• Society: History: By Topic: Social History: Pop Culture (57)

• Teaching the 20th-Century History of the United States
  ericdigests.org
  Provides full-text access to the ERIC Digest of this name which deals with how to teach students about 20th Century American history.
• Do You Remember the 70's, 80's and 90s
  doyouremember.co.uk
  Share your memories of what the 70's, 80's and 90's were really about. Read about what others remember and leave your own memories for others to read.
• The Golden Era
  thegoldenera.net
  American popular culture from the 1930s-1940s. Information and forums covering vintage clothes, cars, music, movies, radio and history.