Definition: Not all phones use the same frequency bands. For instance, GSM cell phones used in Europe work either on the 900 or 1800 megahertz (Mhz) frequency band while American GSM phones use the 1900 Mhz band. Thus, they can't be used in Europe. But most phones today are triband, which means they have all three frequencies and can be used worldwide. Accordingly, in North-America, some CDMA networks use an 800 Mhz frequency band while others work on the 1900 Mhz band. And some cellular carriers use both frequencies on their own territory. For example, a Bell mobility (Canada) customer with a 1900 Mhz phone could not use it in digital technology on parts of Bell's territory where the technology is 800 Mhz
For these reasons, it is always important to take into account the working frequencies of a phone before buying.
Alternate Spellings: Frequency