Integrated on millions of sites, Gravatar is a free service for site owners, developers, and anyone else who wants a verified way to establish their identity online. One picture, rather than who knows how many scattered throughout the internet.
An Automattic project since 2007, Gravatar is built into every WordPress.com account and is widely implemented across the open web.
An optional Gravatar email field is in an Adafruit account holder's profile. If that is filled out, Adafruit may use that picture where you interact with others, such as in the forums or for a user page (if you chose to do so). It's totally optional.