20th century research and practice of science led to advancement in the fields of communication, engineering, travel, medicine, and war. 20th century The 20th (twentieth) century was a century that began on January 1, 1901 and ended on December 31, 2000. It was the tenth and final century of the 2nd millennium. It is distinct from the century known as the 1900s which began on January 1, 1900 and ended on December 31, 1999. The 20th century was dominated by a chain of events that heralded significant changes in world history as to redefine the era: flu pandemic, World War I and
American social dancing in the 20th century to big band music, while jazz dance was done to jazz music. The 20th century brought about a change in social dances. The "old fashioned and out of step" dances such as "the waltz and polka" needed to make way "for something different and new". In the past, only upper class dances had been recorded because lower class dances were "not deemed worthy of record". However, now in the 20th century, "the Industrial Age was upon us, a new middle class was emerging and great social ... innovations were on the horizon". The upper class even became more accepting of