What is GMRS?
GMRS stands for General Mobile Radio Service. It is a specific range of radio frequency channels in the UHF spectrum, specifically 462Mhz to 467 Mhz. An FFC license is required to use GMRS, but unlike amateur radio, a GMRS license from the FCC does not require a test. And the $35 one time fee covers your entire family. With the license, you will be issued a callsign from the FCC that you must transmit for ID when using the system.
FRS vs GMRS
FRS stands for Family Radio Service, and it is another division of the radio spectrum offered by the FCC. FRS and GMRS actually share the same channels (frequencies), but FRS does not require a license... The "walkie talkies" you would find at Wal-Mart etc are typically FRS radios.... GMRS radios can communicate with FRS radios on the same channels.
So why GMRS over FRS?
Great question. The two are interoperable, but your GMRS license, and your GMRS radio, is far more capable than any FRS radio. FRS radios are limited to 1/2 watt to 2 watts, depending on the channel. And FRS radios are not capable of communicating with repeaters... GMRS radios on the other hand can range from 5 watts (handheld/walkie talkie) to 50 watt mobile and repeater stations... Most FRS radios have ridiculous range claims of up to 38 miles (truth is you'll get a mile if you're lucky). But GMRS radios do actually communicate many miles in ideal conditions, and 60 miles or more with the aid of a high powered repeater like ours.