Abstract
The twentieth century was a century of progress. During those hundred years, humanity progressed from a world without airplanes, computers, or modern medicine to a new era in which these technological miracles were commonplace. These technical achievements were not the only accomplishments of that fateful century. There also were vast changes in social thought, with great steps forward toward human equality and freedom — the struggle for racial equality, the recognition of women's rights, and the defeat of the new, unprecedented menaces of Nazism and, in many places, of Communism.