1) The Great Barrier Reef in Australia is the largest living structure on Earth and can be seen from space.

2) DNA, the building block of life, can store incredible amounts of data. It is estimated that one gram of DNA could potentially store about 215 petabytes of data.

3) The most-watched TV series finale in the United States was "MAS*H," with an estimated 105 million viewers.

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