Katrina, Talim and all that...

Firstly, condolences to all affected by mother nature and her temperament.

Ever wondered how typhoons and hurricanes are named? And, what is the difference between a typhoon and a hurricane?

http://www.nhc.noaa.gov/aboutnames.shtml gives the naming convention, which, apparantly differs between regions of the world.

As to the second question, the good people at http://www.usatoday.com inform us that

-quote-
Hurricanes are tropical cyclones in the Atlantic Basin (Atlantic, Caribbean Sea and Gulf of Mexico) and in the Pacific east of the International Date Line.

Typhoons are tropical cyclones over the northern Pacific west of the date line.

Tropical cyclones in the South Pacific and over the Indian Ocean are just called cyclones.
-unquote-

There you have it. Somewhat like the elevator and the lift, the serviette and the napkin, the basement and the cellar. And so forth.