A ham radio or aka amateur radio is a form of radio communications where the radio operator must have a license to transmit on authorized frequencies or bands.
A short-wave radio is a HF receiver (high frequency) that receives between 3, 000–30, 000 kHz. Shortwave radio received its name because the wavelengths in this band are shorter than those used for medium and low frequency bands first used for radio communications. Numerous world-wide radio broadcasting exists here such as the famous BBC and Voice of America.
A CB is a transceiver that operates in the 11 meter band (27MHz). This form of communications is open to anyone and is regularly used by truckers.
There are other types such as marine radio, used by boats, ships, and the Coast Guard. There are GMRS (General Mobile Radio Service) which is used by licensed people and businesses. FRS (Family Radio Service) is a lot like cb in which it is open to everyone but the radios use very low power output.