http://en.gravatar.com/ is part of the Automattic family which is the home of the most used CMS in the world, WordPress. Gravatar is made from the fusion of Graphic and Avatar and it stands for Globally Recognized Avatar. An avatar is nothing but an image which represents a person online. The advantage of Gravatar is that an individual needs to create a gravatar profile just once and then she can sign into any of the websites using gravatar with that profile.
It provides freedom to the individuals from creating an account on every WordPress site on which they want to comment. It is a free service for site owners, users as well as developers. It is included by default in every WordPress.com account.
It is a very popular service and is used by millions of websites around the World Wide Web. The profile of a person includes the uploaded image, name as well as other profile details which the person has chosen to include in their profile. It is very easy to edit the profile by logging in at Gravatar.com and making changes to the profile under my account.
Even though all of the Gravatar profiles are public by default, it is possible to make your profile private by making changes in the settings. There is an option under the view my profile screen on the my account tab. One just needs to click the hide my profile button once and the profile will be hidden.
The Gravatar website lists a variety of resources for helping developers to include gravtars in their own applications. They maintain a list of various plug-ins, libraries and implementations as well as code samples and reference implementations in various languages. So far, they have code samples for Java, PHP, Python, Ruby, Cold fusion,.net and many others such languages.
There is also a detailed help section for the end users on its website. This section answers various common queries of the end-users such as detailed instructions to sign up and making changes in the profile.
Gravatar is available in many languages which include Albanian, Arabic, French, Spanish, Greek, Chinese, Dutch, Indonesian, Italian, Japanese and many others.
The development team at Gravatar also runs a blog on the website which provides updates on the various new developments and features added to the application.