General Packet Radio Service (GPRS)
General Packet Padio Service (GPRS) is a packet data service on the 2G and 3G cellular communication systems Global System for Mobile communications (GSM). The service provides TCP/IP networking over cellular networks and is used as a one of the communications bearers for devices on Xlocate.
You can read more on the technical aspects of GPRS here on Wikipedia.
Xlocate and GPRS
Xlocate uses GPRS based vehicle trackers such as the Thorcom VLR200 and Matrix MTX65G. These devices have their own SIM card and network connection and hence their own tariff and typically connect to the network via a dedicated Access Point Name (APN).
Xlocate also works with Smartphones, tablet PCs and laptop PCs that are location-aware and have their own GPRS connection. In most cases these devices use the network operator's default Internet APN and send location updates via the Internet to Xlocate.