Walkie Talkie is a two way radio to communicate with people of your group without any charges. If you go for outdoor activities, work in a school, go on hiking, working on site etc, you will find that walkie talkies are great to keep in touch with each other on a trip. If you move around from one point to another within a range, you will get walkie talkie useful in this regard.

Walkie-talkies are battery-powered transceivers, meaning they can both send and receive radio messages. They have a half-duplex channel, which indicates that only one walkie-talkie on a channel can transmit a signal at one time, although many radios can receive that same signal. In other words, unlike your phone, in which both parties can interrupt or add to the conversation in a ceaseless flow of sound, walkie-talkies use a push-to-talk (PTT) system -- you have to press a button in order to speak, and you have to release that button to hear sound coming from other units.