usb hid specification
  The USB Human Input Device (HID) Specification is a way to transfer data between your computer and different devices such as a keyboard, mouse, and game controller. The USB HID Specification works by having your computer send out messages telling the device how to behave and the device then responds with its current state. The messages sent by the computer can be things such as: “Hey mouse, move to the left” or “Hey game controller, press the X button”. The device will then interpret the messages, perform the action and send back information to the computer, such as “I moved the mouse to the left” or “I pressed the X button". This way the computer and device can communicate with each other and the computer can understand what the device is trying to do.

hum that doesn't seem right.