Amateur radio, commonly known as ham radio, involves the utilization of specific radio frequency spectra for a variety of applications, including private recreation, the non-commercial exchange of messages, wireless experimentation, self-training, and crucial emergency communication. The term "amateur" is employed to characterize those individuals who engage with radio technology driven solely by personal interest and without the pursuit of direct monetary gain or other similar incentives.The use of "amateur" also serves to distinguish this practice from a range of other radio services that are operated on a professional or commercial basis. These include commercial broadcasting, where programming is produced and transmitted for the purpose of entertainment or information dissemination to the general public, often funded by advertising revenue. Public safety services, such as those operated by police and fire departments, also utilize specific radio frequency spectra for mission-critical communications, coordinating responses to emergencies, and ensuring the safety and well-being of the public.In addition to these, there are professional two-way radio services such as those used in the maritime industry for ship-to-shore and ship-to-ship communication, aviation where air-to-ground and air-to-air communication is vital for safety and coordination, and in taxi services for efficient dispatch and route management.