Changes

The surfaces by the late 19th century and early 20th century had now become standardized. Clay, lawn, and concrete courts were now the most common types of surfaces played on. Other major changes occurring were the clothing. For women, their skirts increasingly grew shorter from the 1920s and on, while for the men their clothing became less formal and more conducive for running.<ref>For a history of clothing and tennis equipment, see: Lake, R. (2015). A social history of tennis in Britain. London: New York, NY.</ref>

Changes to tennis in the early 1900s mostly relate to the development of tournament play and international tournaments developing. One of these was the Davis cup that first held its tournament in 1900. By the 1920s, the four major tournaments, Wimbledon, the US Open, the French Open, and the Australian Open, had developed and remain as the four most important tournaments in tennis. The US open developed in 1881, the French Open in 1891, and the Australian Open in 1905. <ref>For a history of the major tournaments, see: Collins, B., & Hollander, Z. (1994). Bud Collins’ modern encyclopedia of tennis. Detroit: Gale Research.</ref> Although in the 19th century the masses began to play tennis more, it was still largely a sport of the upper classes. What changed this was the Great Depression. During this time, public works projects in the United States in particular included building tennis courts in schools and public areas. This helped more people to take up the game of tennis, increasing its popularity. Tournaments were now held not just in exclusive clubs but in other areas as well. The development of professional international organizations paved the way for international tournament play, standardization, and the modern professional game of tennis at international levels. <ref>For more on how tennis became the sport of different classes, see: Baker, W. J. (1988). Sports in the Western world (Rev. ed., Illini books ed). Urbana: University of Illinois Press, pg. 228.</ref> The International Lawn Tennis Federation, later renamed the International Tennis Federation, developed in 1913. Tennis featured in the 1924 Olympics, although it did not reappear again until 1984. In 1968, the Open Era began when amateurs and professional athletes competed in the major tournaments.<ref>For history on the International Federation, see: Bowers, C. (2013). The international tennis federation: a century of contribution (1st ed). New York, NY: Rizzoli International Publications, Inc.</ref>