Madam Sharmila Bose Jee
I must Congratulate you first for asking very important question . I will try to give reply from Scriptures itself
1. Avatar according to common Hindus

a. Common Hindus have the following concept of Avatar. Avatar is the Sanskrit term where Av means down and tr means passover. Thus Avatar means to descend down or to come down. The meaning of Avatar in the oxford Dictionary is, (In Hindu Mythology) the descent of a deity or released soul to earth in bodily form. In simple words, Avatar according to common Hindus means Almighty God coming down to earth in bodily form.



A Common Hindu believes that God Almighty comes down to the earth in some bodily form to protect the religion, to set an example or to set the rules for human beings.
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Avatars are basically exceptional human beings. In the religion and spiritual world when someone turn out to be a genius then his followers give that person a status of incarnation of God. Looking at his exceptional skill and leadership quality they think it is God Himself who has come down in the form of Human being and call that person an avatar. For instance followers of Sri Ramakrishna , Sai Baba, Sri Sri Ravishankar etc consider them as Avatar. So far I am concerned, going by the Advaitha Philosophy, since every body has Atma which is a part of Paramatma (the Supreme Being) then every living being is an Avatar. If only genius are to be considered as Avatar than Newton, Eisenstein, C V Raman, Pascal, Marconi , Edison, Bose (I mean Satyandranath and J C not Sharmila :) ) etc etc should also be considered Avatar.

They are amongst us....sometimes we recognise and identify them and most of the times we fail to....when any act/deed of any of the individuals are considered to be for the well being of the masses of the society, from the prospective of different religions , they are supposed to be given the name of avatars, belatedly....wat I feel when a person recognise the fact that he is simply a delegate of the Almighty, being sent to earth for completing the delegated task for the well being of the society, that person itself is not less than a avatar for the socity...but a simple thing is being overlooked by most of us...

Avtars are role-models. They are the margdarshies.