Magic (or sorcery) is true and real. It exists and is a reality. It takes place, through Allaah's will and decree, when magicians and sorcerers give obedience, servitude and worship to the devils (shayaateen) who then help them to accomplish and achieve whatever it is they desire to achieve.

The Meaning of Magic (Sihr)

The word (السحر), representing "magic" is:

An expression of that whose cause, or way or means is hidden and subtle

In short, it refers to the subtle, hidden, non-discernible causes behind visible effects. That is from a linguistic aspect, and as for is meaning from a legislative aspect, then it is, as Shaykh Salih al-Fawzan explains in his Kitab at-Tawhid (the Book of Monotheism):

It is spells, incantations, speech which is spoken, medicines (potions) and mist, smoke. And it has a reality (it is real). And from it is that which affects the hearts and bodies such that they become ill or are killed, and (it results in) the separation of a man and his wife. It's effect occurs by the permission of Allaah that relates to the decree in [His] creation. And it is a demonic practice. Most of it cannot be attained except through Shirk (worshiping others alongside Allaah), and seeking nearness to filthy (evil) spirits through what they love, and making use of them through associating them as partners [with Allaah in worship].

Magic Comes In the Garb of "Healing"

Regarding the mention of "medicines", this is in reference to what is historically associated with witchcraft of the science of "alchemy" which delves into spiritual and philosophical areas, and the use of medicinal potions and the likes as part of magical practices. Magicians often come in the garb of "physicians" and "healers". Shaykh Salih al-Fawzan explains a little later:

And from what is obligatory to be aware of and to notify others with is that the magicians, soothsayers and diviners fool around with the beliefs of the people in that they come with the appearance of being doctors, physicians. So they command the ill-person to sacrifice to other than Allaah, in that they sacrifice a young lamb whose feature is such and such, or a chicken. Or they write talismans containing shirk (the association of partners with Allaah) for them, and demonic incantations in the form of amulets that they hang around their necks, or place them in their boxes (trunks, cases, chests) or in their homes.

The Types of Magic

And magic is of two types a) that which is real and b) that which is imaginary. And what is meant by "real" is that a tangible effect is produced by magic, such as a man separating from his wife, or a person becoming ill, or dying and so on. These are all real effects of magic. And as for what is "imaginary", then this is when a person imagines that he has done something he has not actually done, or he is seeing something that is not really like the way he is seeing, so his mind or his eyes have been bewitched.

There are also certain feats that some people perform such as people stabbing themselves with no flow of blood, or turning some objects into others, and swallowing swords, and eating or walking through fire and the likes. Some of these are merely tricks which deceive the eye, and others involve the use of the devils.

The Ruling on Magic

Magic is haraam (unlawful) and kufr (disbelief), because Allaah has stated that the magician (witch, sorcerer) will have no share of the Hereafter and this ruling is found emphatically in a single verse (amongst others).

Allaah, the Most High, said, in the verse in Surah al-Baqarah regarding Sulaymaan (alayhis salaam), the Angels Harut and Marut and Babylon (Baabil):

وَمَا كَفَرَ سُلَيْمَانُ وَلَكِنَّ الشَّيَاطِينَ كَفَرُوا

And Sulayman did not disbelieve but the devils disbelieved...

إِنَّمَا نَحْنُ فِتْنَةٌ فَلا تَكْفُرْ

We (the two Angels, Harut and Marut) are a tribulation so do not disbelieve...

وَلَقَدْ عَلِمُوا لَمَنِ اشْتَرَاهُ مَا لَهُ فِي الآخِرَةِ مِنْ خَلاقٍ

And they knew that whoever purchased of it (magic), that he would have no share of the Hereafter. (al-Baqarah 2:102)

This is because magic is done with the assistance of the Shayaateen (devils, demons), and it does not takes place except through disbelief (kufr), associating partners with Allah (shirk), worship of the devils and worship of the stars.

Magic is From the Seven Destructive Sins

In the hadeeth narrated by al-Bukhari, Muslim, an-Nasaa'ee and Abu Dawud:

From Abu Hurairah that the Messenger of Allaah (sallallaahu alayhi wasallam) said: "Avoid the seven destroyers". They (the Companions) said, "O Messenger of Allaah, what are they?". He said: "Shirk (associating partners) with Allaah (in worship), magic, killing a soul whose killing Allaah has made unlawful without due right, consuming interest (usury), consuming the wealth of an orphan, fleeing from the battlefield, and accusing the believing, unaware, protected (married) women."

In this hadeeth, the Messenger (alayhis salaam) put magic next to shirk (associating partners with Allaah in worship), since magic requires the assistance of the devils and this only takes place through obeying and worshiping them.