No, a daemon is any lesser deity or spirit, it's not connected to Hades unless it's a hero or Chthonic (underworld) daemon, for instance Amphiaraus he died a hero, underwent apotheosis, and became a oracular demigod or daimon of Oropos, there's also abstract personification like Alatheia (truth).
ah sorry thanks for the correction. I do seem to recall very well that the big deal behind the naming, however, was that daemon's were used to communicate messages in the mythology and background services more or less do that (some kind of event)
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https://en.m.wikipedia.org/wiki/Daemon_(computing)