Satnav - Glossary and Terms

Bluetooth A wireless connection common in mobile phones. Used for making calls through your sat nav such as places of interest.
Fixed Satnav see In-Car satnav.
GPS Global Positioning by Satellite. More than two dozen GPS satellites broadcast precise timing signals by radio to GPS receivers, allowing them to accurately determine your satnav's location in any weather, day or night, anywhere on Earth.
Gatso Common name for the most common roadside speed cameras, named after former rally driver Maurice Gatsonides, who invented the system, ironically to help him practice where he could go faster. Some satnavs will display the location of satnav locations.
In-Car Satnav A fixed unit that is installed permanently into the car. Typically they replace the existing audio units, and have pop-out displays.
LCD Liquid Crystal Display. A type of screen commonly found in small electronic devices.
POI Point of Interest. usually displayed by an appropriate icon on the map to indicate a place that may be of interest to the driver, such as car parks, petrol stations, restaurants
Speed Pulse A cable or wire from the vechile management unit that indicates the speed that the vehicle is travelling. Used in installations of in-car satnav units.
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 navigation system. 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.
RDS Radio Data System, see TMC.
SD Secure Digital memory card. Typically maps for additional countries are supplied on SD cards.
Touch Screen A display that is sensitive to human touch. The user can interact with the GPS display by touching words or pictures on the screen.
USB Universal Serial Bus.The interface that connects the satnav to a computer for map and software updates.