Gravatar is a free service for providing globally unique avatars. It is a type of avatar—an image or picture which represents an individual when they interact with websites, and is integrated it into the WordPress blogging platform.
Gravatars were created by Tom Preston-Werner and has been ran and supported by a free service called Automattic since 2007. It’s included with every WordPress account, and always lets every user to authenticate themselves during login, comments are manage not only WordPress, but hundreds of other websites that use it.
“Gravatar” stands for Globally Recognized Avatar, because it works as a single person across multiple websites, removing the need for multiple separate accounts and bios. Prior to Gravatar and similar services, an avatar would included a person’s name. The picture and bios associated with their logon credentials on only a single site.
A gravatar is different than the similarly-named blavatar, which represents an individual blog—not a single person.