1) Michael Jackson's album "Thriller" is the best-selling album of all time, with estimated sales of over 66 million copies worldwide.

2) The world's largest species of shark, the whale shark, can reach lengths of up to 40 feet (12 meters) and weigh over 20 tons.

3) The Sahara Desert, located in North Africa, is the largest hot desert in the world, covering an area of about 9.2 million square kilometers (3.6 million square miles). It is characterized by vast stretches of sand dunes, rocky plateaus, and extreme temperatures.

4) The word "flower" contains two vowels: O and E.