Cell phones are mobile hand-held devices that can be used to contact people next door or in the next country.
Each cell-phone service provider has a network of bases, or cell sites. These sites have antennas on towers, poles, or buildings to receive radio waves. When a call is made, voice and data are sent to and received at the nearest cell site (about ½ to 10 miles away). From there, they go to a switching site and then to the phone being called (if it is on the same network) or to the public telephone network, which connects to other service providers’ networks. As phone users move about, the phone automatically connects to the nearest cell site.
