The ducky is a device used to perform an HID attack where the computer is forced to trust the medium of communication like the mouse or the keyboard where there is an implicit trust between the user and the device.
Ducky script is a scripting language used to perform keystroke injection via the usb port of a computer (acting as an external keyboard). The device used to perform these attacks is called a ducky. And in my case I use a chip with usb interaction capabilities (Atmega 32U4).
Many diferent scripts are available online but I made some for fun.