Frequencies in the VHF, UHF, and microwave ranges above 30 MHz variously have been set aside in the United States and other countries for the use of radio hobbyists, or hams, for two-way voice and telegraphy communications. Some hams use inexpensive equipment operating in the unlicensed 2.4 GHz band for local communications, whereas others invest in more serious equipment for long distance, and even intercontinental, communications. Amateur radio service also is known as ham radio, in reference to the term ham that has long been applied to the hand of inept amateur telegraphers, and shortwave radio, in reference to the short wavelength (high frequency) of the permitted signals. See also ham, UHF, VHF, and wavelength.