Detail about IMEI number

IMEI: International Mobile Equipment Identity

The International Mobile Equipment Identity or IMEI (pronounced /aɪˈmiː/) is a number, usually unique, to identify GSM, WCDMA, and iDEN mobile phones, as well as some satellite phones. It is usually found printed inside the battery compartment of the phone. It can also be displayed on the screen of the phone by entering *#06# into the keypad on most phones.

The IMEI number is used by the GSM network to identify valid devices and therefore can be used for stopping a stolen phone from accessing the network in that country. For example, if a mobile phone is stolen, the owner can call his or her network provider and instruct them to "ban" the phone using its IMEI number. This renders the phone useless on that network, whether or not the phone's SIM is changed. However, the phone can be used on other networks.

Unlike the Electronic Serial Number or MEID of CDMA and other wireless networks, the IMEI is only used for identifying the device, and has no permanent or semi-permanent relation to the subscriber. Instead, the subscriber is identified by transmission of an IMSI number, which is stored on a SIM card that can (in theory) be transferred to any handset. However, many network and security features are enabled by knowing the current device being used by a subscriber.