It's a little stick-like device that plugs into the USB port of a blue-tooth (wireless) enabled computer and picks up signals from another blue-tooth device. I use one to transfer photos from my phone or digi-cam to the computer. Great idea - saves loads of time.
a device which when connected to a computer enables u to send or receive data from any bluetooth device. It connects to ur computer thru usb connectors and r very cheap.
USB powered bluetooth transmitter and receiver which lets ur computer, to which is attached, to connect to other bluetooth devices,like laptop,phones.
But a bluetooth dongle cannot connect to another dongle. It has to be a bluetooth device.