WW2

World War II, often abbreviated as WWII, was a global conflict that took place from 1939 to 1945. It involved the vast majority of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis. The war was marked by significant technological advancements, including the development and use of nuclear weapons, and was the deadliest conflict in human history, with an estimated 70–85 million fatalities.

The war began in Europe in September 1939 when Germany, under Adolf Hitler, invaded Poland. The United Kingdom and France declared war on Germany two days later, marking the start of the European theater. The Pacific War began in December 1941 when Japan attacked the U.S. naval base at Pearl Harbor, Hawaii. The war in Europe ended in May 1945 with the unconditional surrender of Nazi Germany, while the Pacific War concluded with Japan's surrender in September 1945 following the atomic bombings of Hiroshima and Nagasaki.

The war had profound and lasting effects on the world. It led to the creation of the United Nations to promote international cooperation and prevent future conflicts. The war also resulted in significant changes in global politics, including the emergence of the United States and the Soviet Union as superpowers. The Holocaust, the systematic genocide of six million Jews and millions of others by the Nazi regime, is one of the darkest chapters of the war. The war also saw the end of colonialism in many parts of the world, with newly independent nations emerging in Africa, Asia, and the Middle East.