1) The Beatles hold the record for the most number-one hits on the Billboard Hot 100 chart, with 20 songs reaching the top spot.

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

3) The Cuban Missile Crisis in 1962 brought the United States and the Soviet Union to the brink of nuclear war during the Cold War.

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