Aarti is generally performed one to five times daily, and usually at the end of a puja or bhajan session. It is performed during almost all Hindu ceremonies and occasions. It involves the circulating of an 'Aarti plate' around a person or deity and is generally accompanied by the singing of songs in praise of that deva or person (many versions exist). In doing so, the plate itself is supposed to acquire the power of the deity. The priest circulates the plate to all those present. They cup their down-turned hands over the flame and then raise their palms to their forehead - the purificatory blessing, passed from the deva's image to the flame, has now been passed to the devotee.
The aarti plate is generally made of metal, usually silver, bronze or copper. On it must repose a lamp made of kneaded flour, mud or metal, filled with oil or ghee. A cotton wick is put into the oil and then lighted, or camphor is burnt instead. The plate also contains flowers, incense and akshata. The purpose of performing arati is the waving of lighted wicks before the deities in a spirit of humility and gratitude, wherein faithful followers become immersed in God's divine form. It symbolises the five elements: 1) space (akash), 2) wind (vayu), 3) light (tej), 4) water (jal), and 5) earth (pruthvi). Communal Aarti is performed in the mandir; however, devotees also perform it in their homes.
Wikipedia.org
Here in the picture people are watching Arti being performed to the Ganges.
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{K:62768} 1/3/2010