1) The speed of light is approximately 299,792,458 meters per second.

2) The Treaty of Tordesillas, signed in 1494, divided the newly discovered lands outside of Europe between Spain and Portugal, leading to the colonization of the Americas.

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

4) The world's first stock exchange was established in Amsterdam in 1602.