USB Wireless Modems which use a mobile telephone system (GPRS, UMTS, HSPA, EVDO, WiMax, etc.), are known as cellular modems. Cellular modems can be embedded inside a laptop or appliance, or they can be external to it. External cellular modems are datacards and cellular routers. The datacard is a PC card or ExpressCard which slides into a PCMCIA/PC card/ExpressCard slot on a computer.
