Amateur radio is a community of people that use radio transmitters and receivers to communicate with other amateur radio operators. The things that amateur radio operators do with their radios are diverse as the people themselves.
Amateur radio operators are often called ham radio operators or simply "hams." (The origin of this nickname is for all practical purposes lost. Although some people still speculate about this, few agree and even fewer care. Amateur radio operators proudly call themselves hams and nobody knows why.) There are about 600 thousand hams in the United States.
Ham radio operators are licensed by the United States Government and enjoy a far more privileges of radio operation than "CB" radio operators do. These men, women and children pride themselves in adherence to protocols and the regulations of the FCC. With the privileges enjoyed by hams come responsibilities and rules for the operation of an amateur radio station. Specifically, there are a few things that hams are not allowed to do:
1) Hams are not allowed to do anything with their radios that makes them money in way. Bummer. Ham radio is a hobby, but that doesn't mean it's completely frivolous. (Read on!)
2) Ham radio operator cannot `broadcast' to the public. This means that ham radio transmissions are meant to be received by other ham radio operators. While a short-wave radios or scanners will allow you to listen to the amateur radio bands, what you will hear is hams talking to other hams and not music or other radio programs of `general' interest.
Within these (and other) guidelines, however, hams are empowered to do just about everything that government and private radio stations are allowed to do.
Talk around the world - With High Frequency (HF) radios hams can talk to other hams in literally any part of the globe.
Talk around town - With small portable VHF and UHF transceivers hams enjoy extremely reliable communications within their local community.
QRP - Communicating with "very low power" is a challenge that many hams enjoy. QRP is usually practiced on the HF bands.
Packet radio - The internet over ham radio? Not really ... but ham radio operators enjoy a digital network of their own, all without wires!
International Morse Code - While the most basic ham radio license does not require Morse Code (or CW), the real world of amateur radio begins on the HF bands with a CW proficiency.
Amateur television - It's just like real television because it is real television!
Slow Scan TV - Send pictures around the world for little or no cost.
Contests - You can put your radio operating skills up against other hams and teams of hams.
Emergency and other volunteer services - Floods, hurricanes, mudslides, earthquakes, ice storms ... when ever `normal' communications go out, hams are ready to use their radios to provide emergency communication services to their communities. In addition, hams use their local communication and phone patch capabilities to notify authorities of emergencies and hazardous conditions.
Satellite communications - Hams have their own satellites ... really! Amateur's satellites are easy too!
Traffic handling - "Ham telegrams" are used to send messages to people around the world at no cost to the sender or the recipient; all done by ham radio operators volunteering their time and resources.
All hams in the United States are licensed by the FCC. The FCC doesn't give the test. Volunteer Examiners give the tests to people that want to become amateur radio operators. These volunteer examiners then file the paperwork with the FCC and your ham radio license is set to you in the mail.
There are many ways to go about preparing for and taking your ham radio license test.
Local Clubs - For those that like a structured approach, many clubs organize meetings and classes to teach the basic skills of radio operation and prepare people for their ham radio license test. At the end of the classes, a test is given. If you pass, you're a ham!
Elmers - An Elmer is the ham equivalent of a "Yoda." Many new hams are taught my other hams. (Helping people is a common thread throughout the ham radio hobby.) An elmer knows the stuff you need to pass your test and will help you prepare. While an Elmer can not give the FCC examination, he or she will be in touch with other hams in your area and know where public examinations are held.
Self-study - It doesn't seem right to tell you about going it alone, because then you're not doing it all by yourself! Taking a class or having an Elmer is a far better way to get your license; and when you pass your test you will already have friends to talk to.