Gravatar = Globally Recognized AVATAR
Gravatar is similar to avatars I see (and despise) on discussion board across the web, but also different. Your gravatar will appear the same across all websites, as long as the site support it, of course. It is nice to go to a new website, see familiar gravatars, and knows that your familiar peoples are visiting the site too. “See gravatar in use.”:http://joshuaink.com/blog/68/get-a-gravatar
Gravatar is attached to your e-mail address, so you need to give the same e-mail address for it to work globally. Almost all the sites out there don’t show your e-mail address, so spam should not be a problem.
*technical:* what got sent to the central gravatar server, to retrieve your gravatar, is not your e-mail address but MD5 hash of it. Thus the gravatar server doesn’t have your address, either. (Otherwise, WOW!)
“Read more”:http://www.gravatar.com/ about Gravatar, “get one”:http://www.gravatar.com/signup.php yourself, and try it in the comment. : )
*updated* “Read”:/node/728 how to implement gravatars in Drupal.