Throughout the history of amateur radio, amateur radio enthusiasts have made significant contributions to science, engineering, industry, and social services. Research by amateur radio operators has founded new industries, built economies, empowered nations, and saved lives in times of emergency. Amateur radio is a hobby and, by law, completely non-commercial. Individual amateur "ham" radio operators pursue the avocation for personal pleasure through building their own radio stations and communicating with their fellows globally, and for self-improvement via study and practice of electronics, computers, and radio and TV wave behavior. Radio amateurs are, thus, "amateurs" in the true sense of the word: pursuit of an activity only for the love of it. Radio amateurs can not broadcast or transmit music and other general public entertainment programming. The amateur radio use of the air waves is for personal satisfaction and for forwarding the "state of the art" of electronics and communication techniques.

The amateur service is one of the oldest radio service and pre-dates regulation of radiocommunication. In , amateurs could use any frequency above 1. Today, the amateur service operates in relatively small allocations throughout the spectrum. Self-training is an important purpose of the amateur services, as articulated in the definition of the amateur service in No. Radio amateurs have made significant technical contributions to the fields of radio propagation, high frequency single sideband radiotelephone, HF data communications, packet radio protocols and communication satellite design.

Amateur radio , also known as ham radio , is the use of radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport , contesting , and emergency communication. The term "amateur" is used to specify "a duly authorised person interested in radioelectric practice with a purely personal aim and without pecuniary interest;" [1] either direct monetary or other similar reward and to differentiate it from commercial broadcasting , public safety such as police and fire , or professional two-way radio services such as maritime, aviation, taxis, etc. The amateur radio service amateur service and amateur-satellite service is established by the International Telecommunication Union ITU through the Radio Regulations. National governments regulate technical and operational characteristics of transmissions and issue individual stations licenses with a unique identifying call sign , which must be used in all transmissions.