Naming of tropical cyclones
Tropical cyclones with winds exceeding 33 metres per second are given names. These names are taken from lists which vary from region to region. The lists are decided upon either by national meteorological organizations, or by committees of the World Meteorological Organization.

To help in their identification, in the early 1950's the practice of naming tropical storms and hurricanes was initiated by the United States National Hurricane Center and are now maintained by the WMO. In keeping with the common English language practice of referring to inanimate objects such as boats, trains, etc., using the female pronoun "she", names used were exclusively female. The first storm of the year was assigned a name beginning with the letter "A", the second with the letter "B", etc. However, since tropical storms and hurricanes are primarily destructive, some considered this practice sexist. The National Weather Service responded to these concerns in 1979 with the introduction of male names to the nomenclature. Currently, female and male names during a given season are assigned alternately, still in alphabetic order. The "gender" of the first storm of the season also alternates year to year. The lists of names is prepared in advance, and reused periodically, except that the names of particularly destructive storms are "retired".

Other sets of names are used in the Eastern North Pacific, Central North Pacific, and the Western North Pacific, maintained by the WMO Typhoon Committee. The Australian Bureau of Meteorology maintains three lists of names, one for each of the Western, Northern and Eastern Australian regions. There are also Fiji region and Papua New Guinea region names. The Seychelles Meteorological Service maintains a list for the Southwest Indian Ocean.

http://en.wikipedia.org/wiki/Typhoon#Naming_of_tropical_cyclones