Answer:
It is the practice of evicting demons or other spiritual 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.
Amongst christians - 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, and religious material, such as set formulas, gestures, symbols, icons, amulets, etc. The exorcist often invokes god, jesus and/or several different angels and archangels to intervene with the exorcism. Exorcism is primarily associated with the catholic church, although non-catholic christians also claim to perform exorcisms.
Amongst hindus - The practice of exorcism are prominently connected with the ancient dravidians in the south. Of the four vedas (holy books of the Hindus), the atharva veda is said to contain the secrets related to magic and medicine. Many of the rituals described in this book are for casting out demons and evil spirits. These beliefs are particularly strong and practised in west bengal, orissa etc. The basic means of exorcism are the mantra and the yajna used in both vedic and tantric traditions. Vaishnava traditions also employ a recitation of names of narasimha and reading scriptures (notably bhagavata purana) aloud. According to gita mahatmya of padma purana, reading the 3rd, 7th and 8th chapter of bhagavad gita and mentally offering the result to departed persons helps them to get released from their ghostly situation. Burning incense IS offered during a puja, sprinkling water from holy rivers, and blowing conches used in puja are associated practices. Main puranic resource on ghost- and death-related information is garuda purana.
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