1) The word "computer" contains three vowels: O, U, and E.

2) The world's oldest living plant is believed to be a clonal shrub called "Old Tjikko" in Sweden, estimated to be over 9,500 years old.

3) The assassination of Archduke Franz Ferdinand of Austria in 1914 triggered the start of World War I.

4) The Age of Exploration, during the 15th and 16th centuries, saw European explorers such as Christopher Columbus and Vasco da Gama reach new lands and establish trade routes.