A mobile data terminal (MDT) or mobile digital computer (MDC) was a computerized device used in vehicles to provide data communication. They were also used to with specialized radio or cellular communications to display GPS mapping and provide realtime information, MDT's were usually expensive custom built computing devices. Today the MDT or MDC are typically Panasonic TOUGHBOOK laptop or tablet computers securely mounted in a vehicle port replicator (docking station).

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