Packet radio
Packet radio is a form of packet switching technology used to transmit digital data via radio or wireless communications links. It uses the same concepts of data transmission via Datagram that are fundamental to communications via the Internet, as opposed to the older techniques used by dedicated or switched circuits.
Purpose and advantages
Packet radio is a digital radio communications mode. Earlier digital modes were telegraphy (Morse Code), teleprinter (Baudot code) and facsimile. Like those earlier modes, packet was intended as a way to reliably transmit written information. The primary advantage was initially expected to be increased speed, but as the protocol developed, other capabilities surfaced.
By the early 1990s, packet radio was recognized as a way not only to send text, but also to send files (including small computer programs), handle repetitive transmissions, control remote systems, etc.
The technology itself was a leap forward, making it possible for nearly any packet station to act as a digipeater, linking distant stations with each other through ad hoc networks. This makes packet especially useful for emergency communications. In addition, mobile packet radio stations can automatically transmit their location, and check in periodically with the network to show that they are still operating.