The word conjuration (from Latin 'conjure', 'conjurare', to swear together) can be interpreted in several different ways: as an invocation or evocation (the latter in the sense of binding by a vow); as an exorcism; or as an act of illusionism. The word is often used synonymously with "invocation", although the two are not synonyms. One who performs conjurations is called a conjurer or conjuror.
The text of the charms to be recited to conjure the spirit varies considerably from simple sentences to complex paragraphs with plenty of magic words. The language usually is that of the conjurer's, but since the Middle Ages in Western tradition, Latin was the most common (although many texts have been translated into other languages).
When it is said that a person is calling upon or conjuring misfortune or disease, it is due to the ancient belief that personified diseases and misfortune as evil deities, spirits or demons that could enter a human or animal body; see demon possession.
The notion of the action of a conjuration is traditionally linked to the task of repelling negative spirits away, and protecting an individual, space or collectivity. However, it is also believed by many, particularly in Christian and Islamic societies, that magic, and thus conjuration, is an inherently evil practice. According to these beliefs, conjurers summon demons or other evil spirits to cause harm to people or things, to obtain favors from them, or simply to enter servitude to such beings. The belief in similarly-minded conjurers also exists in belief systems in which magic is not inherently evil, although in these cultures these "black magicians" are not the rule and have opposition among more traditional magicians.
Islam strongly forbids the use of conjuration, because it is seen as an unholy procedure, and therefore to perform it is to give an insult to God. It is also considered to, in the end, harm people more than help them: those who regularly contact demons are believed to go mad through overdosing on power, or being possessed (since demons are thought to be short-tempered beings, and given the opportunity might overpower and enslave the one who summoned them).
Conjuration is such a widespread phenomenon in these regions that special television shows and satellite channels have started broadcasting about it. People will phone in to these shows to ask the resident conjurers to aid them in some way -- by showing them how to make charms, for example, or how to conjure by themselves. Though it is obvious that what is going on is conjuration, the conjurers tend to portray themselves as men of religion to add an air of respectability.
Islam has strongly forbidden this new development, with many imams stating that it is more dangerous than going to a conjurer to get service, because it teaches people how to conjure, and by the time the Dajjal arrives at the end of days people will not be able to differentiate between him and Isa (Jesus), as the Dajjal would impose himself as Isa and trick those who are weak in belief.
"Conjurer" or "conjuror" is still the term for what is today called an illusionist or magician by its practitioners. In the not too distant past, conjurors were suspected of using magic power to create their entertaining illusions and even cast spells. Thus they became "magicians" to the general public, who were superstitious, anxious, ill-informed and uncurious. The term is thus used in (and as the title of) a 2008 movie " Conjurer" to refer to dark spirits.