TMC: The Traffic Message Channel (TMC) is a specific application of the FM Radio Data System (RDS) used for broadcasting real-time traffic and weather information. Data messages are received silently and decoded by a TMC-equipped car radio or navigation system, and delivered to the driver visually or as human speech in the preferred language of the user. TMC messages can be filtered so that only those relevant to the current journey are displayed, while a TMC-enabled navigation system can offer dynamic route guidance - alerting the driver of a problem on the planned route and calculating an alternative route to avoid the incident.