An Eyes-Up Display (EUD, pronounced "Yudie") is an optic nerve implant, used in conjunction with a Headcomputer or other device to display a system interface over the user's vision.
An EUD usually does not limit the input methods of its attached device, but generally adds the capability to send some inputs via eye movement.
Those who make heavy use of eye movement input in public, to the detriment of their attention to surroundings, gives Yudie users a generally bad reputation. The practice is considered accident-prone or rude, on a level slightly lower than that of Sleepwalkers.