Respect for written material
In India, it is customary that, out of respect, when a person's foot accidentally touches a book or any written material (which are considered a manifestation of Saraswati) or another person's leg, it will be followed by an apology in the form of a single hand gesture (Pranāma) with the right hand, where the offending person first touches the object with the fingertips and then the eyes, forehead and/or chest. This also counts for money, which is considered a manifestation of the goddess of wealth, Lakshmi.
Source : http://en.wikipedia.org/wiki/Saraswati
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