Dongle may refer to any of the following:
1. A dongle is a cord that hooks up PC Cards to external connections, namely to network cables (RJ-45) and phone lines (RJ-11). A dongle may also be a small hardware device that connects computers to wireless Internet, or other machines via Bluetooth. The picture shows a Bluetooth dongle can connect to a desktop or laptop via a USB (universal serial bus) port.
2. With copy protection and software programs, a dongle is a hardware device that attaches to a computer containing a unique electronic number. These devices are used with high-end programs to help verify the program was legitimately purchased. Because these devices are difficult to recreate, it makes pirating these programs or using the programs on more than one computer almost impossible.
3. A dongle is a device allows the computer to be locked using either hardware or software to prevent unauthorized use.