There seems to be a problem serving the request at this time. Every Ham radio has a maximum output depending on the band being used. The more efficiently it can use that power, the more range you can get out of your radio. All radio communications base on the idea that if you transmit a varying signal someone else can decode the variations and get information that way.
This is not an exhaustive list since there are new radios being introduced every year with additional capability. FM is the most popular mode primarily due to the wide availability of FM repeaters. These repeaters extend the operating range on VHF and enable low power handheld transceivers to communicate over miles.