In speech telephone or two-way radio systems, a system in which the user is required to keep a switch operated while talking. In two-way radio, PTT operation must be used when the same frequency is employed by both transmitters. For use in noisy environments, or for privacy, some telephone handsets have push-to-talk switches that allow the speaker to be heard only when the switch is activated.
At the push of a button on a Push To Talk (PTT) capable phone, the mobile becomes a walkie-talkie, allowing users to talk to other users in their group who are logged in, without having to make a phone call.
A type of communication whereby audio transmission is gated by the user's pressing a designated key (or button) on the voice end point before and during speaking.