what is dongle?

 dongle: soft protector, referred to as soft dog. Dongle is often regarded as hardware protection. It is a small plug-in program that can be attached to the computer's parallel port, serial port, or USB. It contains a manufacturer-burned EPROM and a customized dedicated integrated circuit. On the computer side, dongle = hardware key, which is mainly used to prevent the misappropriation of software. It is like a watchdog, so it is commonly called "dog". The Chinese name may be called the "copyright key", but it can also be considered as "blocking the dog" for the effect of collecting sound and meaning.