According to a 2011 estimate shared by ARRL, there are over 600,000 radio amateurs in the United States and around two million people self-proclaimed amateur radio lovers across the world.
Before you can get on the air, you need to be licensed and know the rules to operate legally. US licenses are good for 10 years before renewal and anyone may hold one except a representative of a foreign government. In the US there are three license classes—Technician, General and Extra.
Technician License
The Technician class license is the entry-level license of choice for most new ham radio operators. To earn the Technician license requires passing one examination totaling 35 questions on radio theory, regulations and operating practices. The license gives access to all Amateur Radio frequencies above 30 megahertz, allowing these licensees the ability to communicate locally and most often within North America.
General License
The General class license grants some operating privileges on all Amateur Radio bands and all operating modes. This license opens the door to world-wide
Extra License
The Extra class license conveys all available U.S. Amateur Radio operating privileges on all bands and all modes.