1) The word "piano" contains three vowels: I, A, and O.

2) The naming of cyclones varies depending on the region. For example, cyclones in the Atlantic and eastern Pacific Ocean are named using a predetermined list of names.

3) The world's largest desert is the Sahara Desert in Africa, covering an area of about 3.6 million square miles (9.4 million square kilometers).

4) The Indian Ocean is the third-largest ocean and is characterized by its warm waters and diverse marine life.