Holy Quran talked about beings called "Jinn" and allocated one chapter (Soura) which holds same name, According to Islamic beliefs; Jinn are intelligent beings created from smokeless fire which means the blue flame at the top of the great fire as described in the Holy Quran (Is Jinn sort of electromagnetic or Infra-red waves) and they are highly evolved from fire to the ethereal form, such as air, although their density increases very few than the air such as the human beings have been evolved from clay to the bone and flesh and blood, Jinn have the ability to reproduce, they are males and females, and they have ability to transform their shapes into animals such as dogs, cats and snakes, or into humans or into other un-earthy entities begins, and they are divided into tribes. By the way, most muslims believe that Jinn are behind the ghosts phenomena, so Jinn can be Islamic equivalent of ghosts or spirits known in western and other cultures around the world .
Their Devine
The Jinn are considered as in charge of creatures as the sons of Adam, so they can be Muslims, Christians , Jews, worshippers of planets, and those who follow the devil (Lucifer or Satan), or those who are descendants of his tribe.
Their Food
It is believed that their diets vary according to their category, the ones who labeled as Atheists (Kuffar) or demons feed on cattle dung, blood, and foul-smelling fumes, However Muslim Jinns feed on incense of good smell.
Their typesJinns are classified as following: 1 - The Residents (Ummar)This is a type of Jinn haunt or live in houses with living people, they can live in toilets or other rooms of house, and here we can differentiate between two types : good or evil ones, good will not harm living people except in rare cases, and they are usually Muslims or they believe in God, but evil ones can inhabit toilets and they are demons, demons, therefore we must fortify with charm of the malice and evil before entering the toilets and bathrooms.
2 – The Spouse (Qareen)A type of demon who entrusted to the human beings since their first hours of birth until their death and it is called "Qareen" in Arabic, main task of Qareen is to silently whisper and seduce the human beings in order to do evil deeds or sins, Muslims believe that each human has two supernatural spouses, one of them is an angel who lead person to do good things (it is called guardian angel in Christian faith, however is angel is not type of Jinn) and the other one is a demon.
3 – The Giant (Mared)A type of Jinn which is huge in size, but nevertheless, not the strongest in Jinn's , this type had mentioned in Arabian Nights tales and known as "Genie".
4 – The Goblin (Ifreet)This type is considered the strongest in the Jinn's category at all, since it depends on their size as a small imp of gnome can kill a giant genie, Holy Quran mentioned this type when one of them (Ifreet) shown in front of prophet king Solomon (peace on him) and promise him that he can bring the throne of the Queen of Sheba immediately - Quran (27:39).
Flyers and DiversJinn can also be flyers and divers and some of them inhabit in the mountains or in the planets, Some divers of Jinn served prophet king Solomon to collect pearls from depths of sees.
Flayers and Satanic PossessionMany believes that harm caused by Jinn flyers is considered to be the most flagrant type of the Satanic Possession which is difficult to be out of the victim because of the difficulty to be environed by the Islamic exorcist.
Finally, Jinn is persistent belief in Islam and they are supernatural hidden intelligent beings created before human , Jinn live in parallel with us, may be on other astral plane, however we still do not know much about their world, although their existence are not scientifically proven yet, future researches may come with prominent clues, or at least measure their effect on our world.