What is a gravatar?
A gravatar, or globally recognized avatar, is quite simply an avatar image that follows you from weblog to weblog appearing beside your name when you comment on gravatar enabled sites. Avatars help identify your posts on web forums, so why not on weblogs?
How do I get a gravatar?
Signing up for a gravatar.com account is FREE, and all that's required is your email address. Once you've signed up you can upload your avatar image and soon after you'll start seeing it on gravatar enabled weblogs!
Sign up now!
100% secure: Your email is encrypted in MD5, so it's very to decode it.

Demo

Let my email be : admin@thissite.com
Upload your avatar Here
Then Instantly your avatar appears in this site or in any site who use Gravatar. Cool Hien!! : ))
It should look this: