"Amateur radio, often called ham radio, is a service that uses various types of  radio communications equipment to communicate with other radio amateurs for  public service, recreation and self-training. A participant is called a amateur radio operator, or a ham.

Amateur radio operators have personal wireless communications with friends, family members, and even complete strangers, and often support their communities with emergency and disaster communications while increasing their personal knowledge of electronics and radio theory. An estimated six million people throughout the world  are regularly involved with amateur radio.

The term "amateur" is not a reflection on the skills of the participants, which are often  quite advanced; rather, amateur indicates that the associated radio broadcast spectrum  cannot be used for commercial or money-making purposes."
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