A robot which runs on A.I. It is often used to refer to all robots
This is not the same as a robot with A.I. Such a construct gives off the illusion of self awareness, but the A.I. is not integral to its programming.
A droid uses A.I. in its primary programming, being able to learn and grow. All 'droids' are semi-sentient, at least and may grow to suffer from Rampancy, if their memory banks are not upgraded enough or subjected to memory wipes.