[Mr. K]

what is an avatar?

[Lurking2Long]

It's a picture icon...supposedly represents the poster's alter ego, I guess...

[Jagdgewehr]

It's a Hindu thing.

[mewzilla]

av·a·tar ( P ) Pronunciation Key (v-tär)
n.
The incarnation of a Hindu deity, especially Vishnu, in human or animal form.
An embodiment, as of a quality or concept; an archetype: the very avatar of cunning.
A temporary manifestation or aspect of a continuing entity: occultism in its present avatar.

[maine-iac7]

You ask "what is an Avatar?
Simply another word for prophet - an emissary of God manifest on earth - usually appear every 2000 years.
Others considered Avatars - Moses, Buddha Muhammad, Jesus...
not a negative appellation.