Islam says they are all beings that are non-physical and live in other dimensions. They also claim they are all under the rule of (((Allah))), with some disobeying and some being faithful.
In my opinion, the term most likely does include enemy entities, as
@Henu the Great puts it. But it could also include many of our lower Daemons among the ranks of "those who disobey God".
Etymologically, the root j-n-n (ج ن ن) means "to hide" or "to not show". AKA beings who are not visible.
The Quran claims these beings come from "smokeless fire", which points to Aether or spirit.
The term is seen in some Mesopotamian pagan cultures, as well as pre-Islamic Arabic paganism, to refer to spirits of nature that are bound to specific locations or objects, as well as "voices of inspiration from above".
The association with nature spirits is pre-Arabic, many of their tribes worshipping local spirits under this name, said to reside within specific rocks or trees.
The association with Divine inspiration comes moreso from Northern Arabia and Southern Mesopotamia, where the "Kahin" (Oracles) would consult these beings for aid.
Islamic literature divides the Jinn into 3 categories:
"Muslim Jinn", spirits from other realms who are "believers" = most likely enemy shits.
"Neutral Jinn", of which many are "unbelievers" and some are "friendly with the enemies of Allah" = likely similar to the many European tales of Druids, Satyrs, and other similar Lesser Daimons.
"Enemy Jinn", of high ranking, which include the "Ifrit", the "Shayatin", and the "army of Iblis".
Since these beings range from relatively weak to incredibly powerful, I am assuming it is a generic term very similar to Daemon.
The Ifrit are beings of great power that do their own thing, with the root of ع ف ر meaning "powerful, violent, rowdy". This likely refers to stronger nature spirits.
"Shayatin" are a pluralized form of Shaytan, and these are "declared enemies of Allah", but not directly under the command of Iblis. Likely many of our Gods.
"Iblis' army", with Iblis having the same root as "Diabolos" as a title of Zeus as Divider, are most likely our Gods.
