According to Islam there are three categories of intelligent beings in the universe created by Allah:
The first category is that of “Angels”, who are created of Light (Noor).  The second category is that of “Jinns” who are created by Smokeless Fire.  The third category is “Human Beings” who are created from clay.

Verse 2 : 285 Surah- Baqara of the Holy Quran mentions specifically that Muslims must believe in Allah, His Angels and His Books:

'The Messenger believeth in what hath been revealed to him from his Lord, as do the men of faith. Each one (of them) believeth in Allah, His angels, His books, and His apostles'

As a Muslim there are some concepts in Islam that should be believed in even though they may not be visible or can be experienced by everyone. One such concept is with reference to "Jinns", as long as they are mentioned in the Authentic Holy Quran & Prophet's Hadiths.

The word Jinn has been mentioned more than 40 times in the Quran in different forms such as: Janna, Jaan, Al-Jinn & Jinnah therefore their existence has been completely accepted in Islamic Jurisprudence and cannot be denied.

The existence of mysterious creatures ("Jinns"/Spirits) sharing their needs and comforts in our world has always fascinated the "logical" mind of the "intelligent" human beings. The precise details and secrets regarding their origin, natures, roles & activities can be found through the texts of Holy Quran & Prophet's Hadiths.

For additional information refer to Black Magic and Mystery of "Shadow of Jinn" by Janab Mohammed Nadeem. (“ebook on sale soon”  - for more details Contact +91 9008193666)