PTT (Push-To-Talk) - definition
This feature is often used in the walkie-talkie. It is a HALF-DUPLEX communication, so only data/voice messages can be sent or received at a time, not like regular cellular devices where people can talk simultaneously and send/receive data at the same time. In one type, the device is always on and sends/receive data, and in PTT mode user have to push on a specific button to activate the microphone or send a command to send the data/voice message. If the activating button is released it sends the data directly to another user. On phone, there are a few options by using which users can create a mini zone and communicate in between them using Internet/WLAN.