The 20th century transformed the political, social, and economic structures of the world in ways no one could have imagined as the 1800s came to a close.
It was a time of intense and rapid change that stretches the capacity of the imagination: first flight and space flight, the Manhattan Project and the Welfare State, Nietzsche and Freud, the Great Depression and inflation, moving pictures and home computers, the Cold War and terrorism—and war and peace.
"The level of change experienced over a 100-year period is what most defines the 20th century," states Professor Pamela Radcliff.
Even today, more than a century later, that transformation is far from complete. The nations of the third world, at last free from the colonialism and imperialism that once marked their relationship with the West, are still caught up in the even more complex search for politically stable democracy and economic prosperity.