Wireless devices are those devices through which data is being transferred by electromagnetic waves. There are various wireless devices that pass RF signals such as Bluetooth modules, RF modules, Arduino wireless modules, WiFi modules, Zigbee/xbee modules.
A GSM module or a GPRS module is a chip or circuit that will be used to establish communication between a mobile device or a computing machine and a GSM or GPRS system.
GPS modules contain tiny processors and antennas that directly receive data sent by satellites through dedicated RF frequencies.