re:A dongle, also known as an adapter, is a small piece of hardware that connects to another device to provide it with additional functionality or enables a passthrough to such a device that adds functionality.[1] In computing, the term is primarily associated with hardware providing a copy protection mechanism for proprietary software, in which the dongle must be attached to the system on which the software is installed in order for it to function.

The first dongles were attached to the PC parallel port of the IBM PC via the DB-25 Centronics plug to prevent unauthorised use of proprietary software, while still allowing normal operation of the printer.

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-form factor 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.

what is the dongle mean.https://en.wikipedia.org/wiki/Dongle