Generate gravatar url Read more about gravatar: http://en.gravatar.com/site/implement/images/.

a transparent PNG image (border added to HTML below for demonstration purposes).

do not load any image if none is associated with the email hash, instead return an HTTP 404 (File Not Found) response.

a geometric pattern based on an email hash.

a generated 'monster' with different colors, faces, etc.

a simple, cartoon-style silhouetted outline of a person (does not vary by email hash).

awesome generated, 8-bit arcade-style pixelated faces.

generated faces with differing features and backgrounds.