Cell YourselfWireless telephony consists of two parts: a cellular phone and the wireless infrastructure that carries the calls.

To use a cellular phone, you need to subscribe to a wirelessservice provider. When a phone number is assigned and the cellularphone is programmed, all the information needed for the phone andsystem to work together is entered into the cellular phone.

The phone is designed to look for a wireless signal and keep onlooking until it finds one. When a cellular phone is turned on, itlistens to the information that is constantly broadcast by thewireless carrier in what is called an overhead signal. The phonethen matches the overhead signal to the signal identification codein the phone. If they match, your phone rings with the incomingcall.

Excerpted fromStart Your Own Business: The Only Start-Up GuideYou'll Ever Need