1. Man's arrival to the Moon

On July 21, 1969, US commander Neil Armstrong of the manned space mission Apollo 11 of the United States was the first human to step on the moon. As he descended the ladder of the module, Armstrong proclaimed the famous phrase of the story: "This is a small step for man, but a great leap for mankind."



2. First and Second World War

The First (1914-1918) and World War II (1939-1945) were two major conflicts in which chemical weapons were first used, and generated violence, terror and misery. It is estimated that the casualties of the "Great War" were more than 8 million people, while the victims of World War II amounted to 60 million people.



3. Discovery of Penicillin

The British Alexander Fleming revolutionized modern medicine with the discovery of Penicillin, which managed to treat diseases that to date were considered incurable.



4. Tiananmen revolt

It consisted of a series of demonstrations led by students in the People's Republic of China who called for more democracy and freedom of expression, among other demands. Finally, the Chinese army was ordered to intervene and crush the revolt on the night of June 3 to 4. The social cost of repression is estimated in thousands of dead.



5. The fall of the Berlin Wall

It was one of the symbols of the Cold War, which separated West Berlin and the GDR. Many people died in an attempt to cross it. It was on November 9, 1989 when the "Wall of Shame" collapsed.