A walkie-talkie (handheld transceiver) is a portable two-way radio transceiver. It was created during the Second World War by Donald L. Hings and Alfred J. Gross (supported by Motorola). Although walkie-talkies has two channels, only one can be used to talk at the time through a PTT system (push-to-talk), and one of its main characteristics is that it has a speaker so everybody can hear what it's said, not only the person using the walkie-talkie.