1. The discovery of a method of mass production of penicillin, 1943
Pharmacists fill culture flasks with the nutrient solution on which the penicillin mould is grown in 1943.
Photograph: Daily Herald Archive/SSPL via Getty Images
Photograph: Elise Amendola/AP
3. The widespread availability of home computers
A 1980s UK Spectrum magazine advert.
Photograph: The Advertising Archives
4. The United Nations Universal Declaration of Human Rights, 1948
Eleanor Roosevelt, holding the Universal Declaration Of Human Rights, which she helped to draft.
Photograph: Nara Archives/REX
5. The breakup of the Soviet Union in 1991
Soviet army tanks parked in Moscow’s Red Square after a coup briefly toppled the Soviet president, Mikhail Gorbachev.
|breakup of the Soviet Union in 1991|
Photograph: Dima Tanin/AFP/Getty Images
6. The rise in global awareness of the importance of environmental protection/conservation
Vivienne Westwood campaigning with Greenpeace at Glastonbury in 2014.
Photograph: Gary Calton for the Observer
7. The terrorist attacks of 11 September 2001 on New York (the World Trade Center) and Washington DC; and the emergence of terrorism as a major international phenomenon
Looking up from the location of Church and Fulton streets.
|terrorist attacks of 11 September 2001 in New York|
Photograph: Richard Cohen/Corbis
8. The invention of the atomic bomb and the explosion of atomic bombs over the Japanese cities of Hiroshima (6 August 1945) and Nagasaki (9 August)
A mushroom cloud rises more than 60,000 feet into the air over Nagasaki.
|atomic bomb and the explosion of atomic bombs over Japan|
Photograph: Everett Collection / REX
9. The influence of Nelson Mandela (1918-2013) on South African and international politics and society
Mandela stands at the window of the cell in Robben Island prison, where he was incarcerated for more than two decades.
Photograph: Louise Gubb/Corbis
10. The human genome project, completed in 2001, which mapped the genetic structure of the human body
A visitor views a digital representation of the human genome at the American Museum of Natural History in New York City.
Photograph: Mario Tama/Getty Images