Hams are issued a callsign such as KCØXXX to use to identify themselves on the air. A callsign is much like a finger print and is only issued to one person in the world. Hams take great pride in their callsigns and will display it everywhere from clothing to their vehicle license plate.
Hams talk on the radio mostly for fun however there is great emphasis on emergency communications after a disaster such as an earthquake, hurricane, Sept 11 when other forms of communications do not work such as telephones and cell phones. With the proper equipment and license class a Ham can talk around the world.