A device that is capable of operating in two frequencies. On a wireless network, dual-band devices are capable of operating in both the 2.4GHz (802.11b/g) and 5GHz (802.11a/n) bands. In cellular phone technology, dual-band devices typically operate in both the GSM900 and GSM1800 frequencies, allowing a greater number of roaming options
a dual-band mobile phone is able to work in at least two different countries because it can receive two different types of signals