Exorcism is the practice of evicting demons or other supernatural entities from a person or place which they are believed to have possessed. The practice is quite ancient and part of the belief system of many cultures.
In Christian practice the person performing the exorcism, known as an exorcist, is often a member of the church, or an individual thought to be graced with special powers or skills. The exorcist may use prayers, a cross, holy water, etc. The exorcist often invokes God, or higher powers to intervene with the exorcism. Exorcism is primarily associated with the Catholic Church, although non-Catholic Christians also claim to perform exorcisms.
In general, possessed persons are not regarded as evil in themselves, nor wholly responsible for their actions. Therefore, practitioners regard exorcism as more of a cure than a punishment. The mainstream rituals usually take this into account, making sure that there is no violence to the possessed, only that they be restrained if the person is violent.