Star Wars originally established that the weapons used to disable the electronic systems of droids and (on a larger scale) starships were called ion weapons, presumably working by shooting a stream of ions at the target. This is the same effect EMP (electromagnetic pulse) weapons have. Yet, Star Wars also mentions EMP weapons separately from ion weapons.
Examples:
Is there a difference or are these just colloquial, interchangeable terms? I haven't a clue what would happen if you shot a beam of ions at something, but honestly, it sounds far more advanced than an EMP.
This proves you could combine them:
But how are they different, if at all?
