Telematics is an interdisciplinary field that involves the technology of sending, saving, and receiving information by telecommunications or the integrated use of telecommunications and informatics for application in vehicles. The device collects GPS data, as well as an array of other vehicle-specific data. It transmits it via GPRS, 4G mobile data and cellular network, or satellite communication to a centralized server. The telematics data can include location, idling time, speed, harsh acceleration or braking, vehicle faults, and more. Bidirectional means the data flows in both directions, whereas unidirectional means the data flows in only one direction.