Dongle

A dongle is a small piece of hardware that connects to another device to provide it with additional functionality. In relation to computing, the term is primarily associated with hardware providing a copy protection mechanism for commercial software—in which the dongle must be attached to the system that the software is installed on in order for it to function.

The term "dongle" is also associated with similar devices meant to provide additional forms of wireless connectivity to devices (such as Wi-Fi or Bluetooth support), often over USB connections, as well as small digital media players (such as Amazon Fire TV Stick, Chromecast, and Roku Streaming Stick) and personal computers (such as Chromebit and Intel Compute Stick) meant to plug directly into an HDMI input on a television.

(The additional expense of producing the dongle was justified by the high purchase price of the software (hundreds of British pounds) and the tendency for unprotected software to be subject to piracy. To ensure compatibility with MIDI and other audio expansion units that also occupy the single cartridge port, some dongles had a pass-through connector to accommodate them. Some expanders were also designed with backplane sockets to host the different dongles unique to a specific set of packages. Eventually, software pirates were able to circumvent the dongle scheme by modifying the program's binary to accept simulated dongle responses, at the expense of stability and performance.)

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