The WebFinger protocol has its basis in Unix, where someone can run a
finger command on an email address identifier to gain information
about a user. WebFinger has modernized this functionality for the Web 2.0
world, defining a standard for providers to associate metadata with a
user’s email address to access her profiles, activities, and much
Some examples of information providers might associate with a user’s email addresses include:
Links to public profiles for the user.
Direct profile data, such as a nickname or profile photo.
Other linked services for the email address, such as Facebook, Twitter, or Flickr accounts.
These are just a few of the possible links that a provider may implement for metadata, but WebFinger is more focused on building a specification simply to ensure that this metadata is available. The providers themselves determine the amount of information to tie to an email address.