Amateur Radio, also known as Ham Radio.
See: Ham Radio Category
Amateur radio is a hobby and service that allows licensed individuals to explore and engage in radio communication using designated frequencies. Operators, called hams, use various radio equipment to communicate locally, nationally, and globally, employing voice, CW code, digital modes, and other techniques. Beyond its recreational aspect, amateur radio serves as a vital emergency communication resource during disasters, promotes technical learning and innovation, and fosters a community of enthusiasts worldwide.