The term "Allied forces" refers to the military coalition of countries that fought together during major conflicts, most notably during World War I and World War II. This alliance included nations such as the United States, United Kingdom, Soviet Union, and France, among others. Their primary goal was to defeat the Central Powers in World War I and the Axis Powers in World War II. The cooperation among the Allied forces involved sharing resources, intelligence, and military strategies. This collaboration was crucial in achieving significant victories, such as the D-Day invasion in 1944, which marked a turning point in the war against the Axis Powers in Europe.